Full opinion text
TOBRINER, J. Plaintiffs brought these four actions to quiet title to undivided mineral interests underlying section 31, township 16 south, range 11 east, Mt. Diablo base and meridian, in San Benito County (section 31). They claimed these interests as successors of stockholders in two now-defunct corporations, Ashurst Oil, Land and Development Company (Ashurst) and California Oil Products Company (COP), which obtained specified mineral rights in section 31 in 1910. Joseph Gerhard (Gerhard), plaintiff in S.F. 21805, Ira Solomon and others (Solomon), plaintiffs in S.F. 21807, and Herbert Mettler and others (Mettler), plaintiffs in S.F. 21808, claim interests in the mineral rights formerly held by Ashurst. The Kennedy-Weber Oil Company and others (Weber), plaintiffs in S.F. 21806, claim interests in the mineral rights formerly held by both Ashurst and COP. Defendants raised a number of defenses essentially based on their long occupation of the surface of section 31 and the failure of plaintiffs and their predecessors to assert these rights for 47 years until the time that defendants struck oil. The trial court entered judgment for defendants in each action, and plaintiffs appeal. We shall summarize the relevant facts and set forth additional matters as necessary in the body of the opinion. In 1905 the Ashurst family conveyed the Syncline Ranch, which includes section 31, to Abrams and Brandt, who executed a purchase money mortgage for $17,500, which was assigned to the Hollister Savings Bank (Hollister Bank mortgage). Abrams and Brandt had organized two corporations, Ashurst and COP. To Ashurst they conveyed an estate in certain minerals underlying a portion of section 31, and to COP they conveyed a similar mineral estate underlying the remainder of section 31. COP executed a mortgage for $21,610.82 to Abrams and Brandt as part of the purchase price (COP mortgage). Ashurst drilled three dry wells on the property; COP did no drilling. COP in 1912 and Ashurst in 1915 forfeited their corporate charters for nonpayment of taxes; the stockholders succeeded to the title of the corporate property. In 1917 Brandt brought an action to quiet title to the Syncline Ranch. (Action 1870; San Benito County.) The court in 1923 quieted the title of Abrams and Brandt as a partnership in the surface estate in section 31 and in the portion of the mineral estate represented by the partnership’s stock holdings. The court also found that Abrams and Brandt, as individual stockholders, obtained title to fractional interests in the mineral estate at the time the corporations forfeited their charters. It decreed all the stockholders, in proportion to their holdings, were “coowners” of the mineral estate subject to a trusteeship of the directors for liquidation and, in the case of the COP stockholders, subject to the lien of the COP mortgage held by the partnership of Abrams and Brandt. The court ordered the trustees to sell the corporate properties and pay the proceeds into court for the benefit of shareholders and creditors, but it does not appear that this order was ever carried out. In 1919 Brandt brought an action (action 13948; San Joaquin County) for partnership accounting. The court ordered the partnership interest in the Syncline Ranch to be sold; this included the surface estate in section 31, an undivided 114,811/ 366,201% interest in the Ashurst mineral rights, an undivided 199,500/503,000 interest in the COP mineral rights and the COP mortgage. The court included in the decree a copy of a mortgage foreclosure decree in which the Hollister Bank mortgage had been foreclosed and a sale ordered of the Syncline Ranch to pay off the mortgage. The decree in action 13948 proceeded to state that Brandt had paid the Hollister Bank mortgage and, through his son-in-law Mettler, taken an assignment of the mortgage. The court in action 13948 appointed a commissioner, who sold the partnership interest in the Syncline Ranch to Halsey, Brandt’s nephew. In 1924, shortly after the commissioner’s sale, Halsey conveyed to Antonio Prusetta, who had previously been a lessee of the Syneline Ranch, and Warren Cornwell (1) the “whole” of section 31, “subject to” the deeds to Ashurst and COP, (2) the Abrams and Brandt partnership interest in the property conveyed to Ashurst and COP, and (3) the COP mortgage. It was from the proceeds of this transaction that the Hollister Bank mortgage held by Brandt had been discharged. Frusetta and Cornwell, who, prior to 1924, had leased the Syncline Ranch and used it for a cattle ranch, continued to use it for that purpose. Henry Carroll in 1938 obtained a lease covering oil, gas, and other hydrocarbons from the Frusetta-Cornwell defendants but did not undertake any drilling. In 1951 Tillman Hess obtained another lease from these defendants; he drilled a dry hole on the Syncline Ranch; the drilling, however, by inadvertence, did not take place in section 31. Defendant Shell Oil Company obtained the Hess lease and other leases from the Frusetta-Cornwell defendants in 1951 and 1952. The Frusetta-Cornwell defendants, in 1952, brought an action (action 5362) against “all persons unknown” to quiet title to “all of Section 31.” None of the plaintiffs or their predecessors were named or served with process. Following publication of summons, the court in 1953 quieted title in the Frusetta-Cornwell heirs to “all of Section 31.” In 1954 some of Cornwell’s heirs brought an action (action 5591) to quiet title to an undivided one-half interest in section 31 against certain named heirs of Cornwell and “all persons unknown.” As in action 5362, none of plaintiffs or their predecessors were named or served with process. The court quieted title to an undivided interest in section 31 subject to the Shell lease. In 1956 Shell began drilling operations and struck oil on section 31. Plaintiff Gerhard, who had no connection with any of the transactions outlined above, read of the discovery and began investigating the title to section 31. Learning of the interests transferred to COP and Ashurst he approached the successors of the stockholders, obtained some of the claims, and instituted legal action. Other heirs of the stockholders brought separate actions. The trial court entered judgment in favor of defendants. The trial court found that (1) plaintiffs had abandoned their interest in the oil and gas and other fugacious minerals underlying section 31; (2) defendants had acquired title to all the mineral interests by adverse possession; (3) plaintiffs’ claims were barred by laches; (4) plaintiffs’ claims were barred by the decrees in actions 5362 and 5591. Plaintiffs challenge these findings and additionally claim that (5) they were deprived of their right to cross-examine George Frusetta, the son of Antonio Frusetta. (6) The Weber plaintiffs claim that the trial court erred in disallowing a class action. Defendants claim that the trial court’s judgment must be sustained in any event (7) as to all plaintiffs because they had lost their right to redeem under the Hollister Bank mortgage, and, (8), as to plaintiff Gerhard, because he acquired his claims through the unlawful practice of law and through violations of the California Corporate Securities Act. We summarize our holding as follows: (1) Substantial evidence sustains the trial court’s finding that the predecessors of the Weber plaintiffs abandoned their interests in the minerals underlying section 31. As to the remaining plaintiffs, however, we find no such substantial evidence. (2) Defendants did not acquire title to the mineral interests by adverse possession. (3) Plaintiffs are not guilty of laches in asserting their claims. (4) The decrees in actions 5362 and 5591 do not bar plaintiffs’ claims. (5) Plaintiffs were not deprived of their right to cross-examination. (6) The trial court could properly rule that the Weber plaintiffs could not bring a class action. (7) The Hollister Bank mortgage does not cover plaintiffs’ interests in the minerals. (8) Defendants may not be heard to assert that plaintiff Gerhard illegally acquired his claims. Accordingly, we reverse the judgments in S.F. 21805, 21807, and 21808, and the judgment in S.F. 21806 as to Joseph M. Gerhard. We affirm the judgment in S.F. 21806 as to all parties other than Gerhard. 1. Abandonment A. Plaintiffs’ interests are subject to abandonment. The trial court found that “the interests in section 31 claimed by plaintiffs ... to the oil, gas and other fugacious minerals have been abandoned.” Plaintiffs challenge the propriety of this finding. They point to the general rule that legal title to a fee simple can never be abandoned. They now claim ownership of such an estate in the fugacious minerals underlying section 31 and accordingly conclude that such an estate could not be abandoned. Defendants, on the other hand, rely on the general rule that property interests in the nature of incorporeal hereditaments can be abandoned. They so categorize the interests obtained by plaintiffs’ predecessors in the fugacious minerals and therefore contend that these rights are subject to abandonment. Our courts have not spoken on this precise question. Since, however, the question involves title to interests in real property we must, if possible, find our solution within the rich but rigid context of the historical background of the common law and the California cases. As we explain, however, not only the precedents but also the considerations underlying these precedents lead to the identical conclusion: these interests may be abandoned. We shall point out that Abrams and Brandt conveyed to the corporations the exclusive and perpetual privilege of drilling for oil and gas. Under California law we classify such an interest as a profit a prendre, an incorporeal hereditament. We then explain that profits a prendre are essentially indistinguishable from easements and, thus, like easements and other incorporeal hereditaments they can be abandoned. In so holding we reject plaintiffs’ argument that since California cases describe a perpetual profit a prendre as an “estate in fee” such a perpetual interest is not subject to abandonment under the general rule that “fee interests” in real property cannot be abandoned; the cases have used the term fee interest” in two different contexts: (a) to indicate the perpetual nature of the interest; (b) to indicate the possessory, or corporeal, nature of the interest. The cases in which the courts have declared that a “fee interest” cannot be abandoned use the term in the latter sense; the cases that hold that a perpetual profit is a “fee interest” use the term in the former sense. In support of our conclusion we note that the historical reason for the refusal of courts to recognize abandonment of certain interests in real property—the possibility of voids in titles—does not apply here. To the contrary the recognition that holders of ancient titles and their successors may abandon such interests tends to improve the marketability of titles. It removes encrusted impediments to titles and thus permits the present-day sale and disposition of land so that this prime resource may be utilized to the maximum. 1. The deeds gave to plaintiffs the exclusive privilege of drilling for oil and gas, which constitutes a profit a prendre, an incorporeal hereditament. We begin with consideration of the leading case of Callahan v. Martin (1935) 3 Cal.2d 110 [43 P.2d 788, 101 A.L.R. 871], In that case this court definitively resolved the conflict in the early California cases as to the nature of ownership of oil and gas interests in this state. (See Colby, The Law of Oil and Gas (1943) 31 Cal.L.Rev. 357, 384-402.) We there rejected the view held by the majority of concerned jurisdictions that the assignee of an oil and gas interest possesses a defeasible fee in definite corporeal real property. (See, e.g., Texas Co. v. Daugherty (1915) 107 Tex. 226 [176 S.W. 717, L.R.A. 1917F 983] ; see also 1 Williams & Meyers, Oil and Gas Law, §203.3; 1 Kuntz, Oil & Gas, § 2.4, p. 66.) The concept of the defeasible fee, we held, did not sufficiently recognize the practical difference between oil and gas and solid minerals: the latter remain in place beneath the surface of land, but the former, fugacious and vagrant, may be drawn from beneath the surface of other lands. (3 Cal.2d at pp. 116-117.) We held that “an operating lessee under a lease for a term of years . . . has an interest or estate in real property in the nature of a profit a prendre, which is an incorporeal hereditament, and that the assignee of a royalty interest in oil rights under an assignment by the landowner[] also has an interest or estate in real property in the nature of an incorporeal hereditament.’’ (P. 118.) We further stated, “The holders of oil interests under a landowner’s assignments have rights of profit a prendre, which are estates in real property, and are properly described as real property, or real estate, where, as in the instant case, they are to endure in perpetuity.” (Pp. 127-128.) In Dabney-Johnston Oil Corp. v. Walden (1935) 4 Cal.2d 637 [52 P.2d 237], we further elaborated the California position. “The owner of land has the exclusive right on his land to drill for and produce oil. This right inhering in the owner by virtue of his title to the land is a valuable right which he may transfer. The right when granted is a profit a prendre, a right to remove a part of the substance of the land. A profit a prendre is an interest in real property in the nature of an incorporeal hereditament. . . . The profit a prendre, whether it is unlimited as to duration or limited to a term of years, is an estate in real property. If it is for a term of years, it is a chattel real, which is nevertheless an estate in real property, although not real property or real estate. [Citation omitted.] Where it is unlimited in duration, it is a freehold interest, an estate in fee, and real property or real estate. Thus, although the oil and gas in place doctrine is rejected, interests in oil rights which are estates in real property may be granted separate and apart from a grant of surface title.” (Italics added.) (P.649.) With this background we proceed to analyze the grants to the two corporations. We have no doubt that Abrams and Brandt purported to convey to the corporations the entire interest of the partnership in the oil, gas, and other hydrocarbonic substances underlying section 31. As we pointed out in La Laguna Ranch Co. v. Dodge (1941) 18 Cal.2d 132 at page 135 [114 P.2d 351, 135 A.L.R. 546], however, “ [T]he owner of land does not have an absolute title to the oil and gas in place as corporeal real property, but rather has the ‘ exclusive right’ to drill for oil and gas upon his premises.” (See Bernstein v. Bush (1947 ) 29 Cal.2d 773, 778 [177 P.2d 913] ; Tanner v. Title Ins. & Trust Co. (1942) 20 Cal.2d 814, 819 [129 P.2d 383] ; Caffroy v. Fremlin (1961) 198 Cal.App.2d 176, 182 [17 Cal.Rptr. 668].) Since an owner may not effectively transfer rights in property greater than those he himself is able to enjoy (23 Am.Jur.2d, Deeds, § 289), the corporations received no title to the oil and gas as corporeal real property but rather obtained the exclusive privilege of drilling for these substances. This right, as explained by Callahan and Dabney-Johnston, is a profit a prendre, an incorporeal hereditament. Since the right is to endure in perpetuity, it is a “freehold interest, an estate in fee, and real property or real estate.” 2. Plaintiffs’ perpetual profits a prendre, like easements, are subject to abandonment. Following the common law this court has classified profits a prendre, together with easements, as incorporeal hereditaments. (Callahan v. Martin, supra, 3 Cal.2d 110, 118; Schiffman v. Richfield Oil Co. (1937) 8 Cal.2d 211, 223 [64 P.2d 1081].) As we shall point out, for the purposes of the issue now before us, easements and profits a prendre are indistinguishable. “ [T]he term ‘easement’ is so used [in the Restatement of Property] as to include within its meaning the special meaning commonly expressed by the term 1 profit. ’ ... In phrasing the rules applicable to each of these interests it has been found . . . that in no case was there a rule applicable to one of these interests which was not also applicable to the other. ...” (Rest., Property, § 450, Note; Costa v. Fawcett (1962) 202 Cal.App.2d 695 [21 Cal.Rptr. 143] ; Civ. Code, §802.) Substantiating the Restatement’s conclusion, we explain that Callahan and Dabney-Johnston in defining the nature of a perpetual profit a prendre, such as the one involved in the instant case, employed language equally descriptive of a perpetual easement. Thus Dabney-Johnston Oil Corp v. Walden, supra, 4 Cal.2d 637 at p. 649, holds that “ [w] here [the profit] is unlimited in duration, it is a freehold interest, an estate in fee, and real property or real estate.” The California cases have long held that these attributes, employed in Dabney-Johnston to describe a profit, are also characteristic of other perpetual incorporeal hereditaments. Thus in Appeal of North Beach & M. R.R. Co. (1867) 32 Cal. 499, for instance, this court described at some length the nature of an easement: “ [A]n easement is property ... an incorporeal hereditament, but it is still a tenement and an interest in the land. ‘. . . The interest of an easement may be freehold, or a chattel one, according to its duration.’ (Wash, On Easements, 5, par. 5.) ‘An easement must be an interest in, or over the soil.' (Per Cresswell, J., in Rowbotham v. Wilson 8 Ellis and B. 157.) ‘A right of way is an assignable property. It is a real, or chattel interest, according to the term of its duration, and the former is well known in the law as that sort of real property belonging to the class of incorporeal hereditaments. ’ (Ex parte Coburn, 1 Cow. 570; Heaton v. Ferris, 1 John 146.) It is real property, and it is created by grant.” (P. 506.) We also noted that appellant railroad's easement was “an interest in the land—and . . . real estate . . . .” (P. 512.) (See also Corea v. Higuera (1908) 153 Cal. 451, 454 [95 P. 882, 17 L.R.A. N.S. 1018] ; Roth v. Cottrell (1952) 112 Cal.App.2d 621, 625 [246 P.2d 958] ; Balestra v. Button (1942) 54 Cal.App.2d 192, 198 [128 P.2d 816], for descriptions of perpetual easements as real property; Crowell v. City of Riverside (1938) 26 Cal.App.2d 566, 579 [80 P.2d 120] ; Guy v. Brennan (1923) 60 Cal.App. 452, 454 [213 P. 265].) Furthermore, “ [T]he interest in land which an easement constitutes is real property and itself may be held in fee simple . . . .” (Highland Realty Co. v. City of San Rafael (1956) 46 Cal.2d 669, 677 fn. 1 [298 P.2d 15] ; Appeal of North Beach & M. R.R. Co., supra, 32 Cal. 499, 509; City of Glendora v. Faus (1957) 148 Cal.App.2d 920, 921 [307 P.2d 976] ; Ocean Shore R.R. Co. v. Doelger (1954) 127 Cal.App.2d 392, 398-399 [274 P.2d 23] ; Irvin v. Petitfils (1941) 44 Cal.App.2d 496, 500 [112 P.2d 688] ; Eastman v. Piper (1924) 68 Cal.App. 554, 562 [229 P. 1002]; 17 Cal.Jur.2d, Easements, § 2, pp. 90-91.) Thus, as we have noted, the cases have described the perpetual easement and the perpetual profit in identical terms and have treated these interests identically. (See Costa v. Fawcett, supra, 202 Cal.App.2d 695; Rest., Property, § 450, Note.) Although no California authority precisely states whether the perpetual profit may be abandoned, we submit that the cases discussing abandonment of perpetual easements created by grant in real property disclose the appropriate rule. The eases have held that perpetual easements created by grant in real property can be abandoned. (People v. Southern Pac. Co. (1916) 172 Cal. 692, 701 [158 P. 177] ; Smith v. Worn (1892) 93 Cal. 206, 212 [28 P. 944] ; Buechner v. Jonas (1964) 228 Cal.App.2d 127, 131 [39 Cal.Rptr. 298] ; Lake Merced Golf & Country Club v. Ocean Shore R.R. Co. (1962) 206 Cal.App.2d 421, 436 [23 Cal.Rptr. 881] ; Ocean Shore R.R. Co. v. Doelger (1960) 179 Cal.App.2d 222, 231 [3 Cal.Rptr. 706] ; Haley v. Los Angeles County Flood Control Dist. (1959) 172 Cal.App.2d 285, 291 [342 P.2d 476] ; Ocean Shore R.R. Co v. Doelger, supra, 127 Cal.App.2d 392, 403; see Rest., Property, § 504, com. a.) We conclude that profits, like easements, can be abandoned (see Miller v. State (1936) 121 Conn. 43, 48 [183 A. 17] (plaintiff abandoned his right to remove rock) ; Mathews Slate Co. v. Advance Industrial Supply Co. (1918) 185 App. Div. 74, 79 [172 N.Y.S. 830]). In so holding, we follow the general rule that all incorporeal hereditaments can be abandoned. (1 Am.Jur.2d, Abandoned Property, §14; 1 C.J.S., Abandonment, § 5(c) ; see 1 Cal.Jur.2d, Abandonment, § 9.) As the leading authorities in the field of oil and gas law, Professor Williams, Dean Maxwell, and Professor Meyers, have declared, such perpetual profits a prendre, constituting incorporeal hereditaments, were subject to abandonment. “At common law, incorporeal estates but not corporeal estates were subject to extinguishment by abandonment. If the mineral grantee or lessee has merely an incorporeal estate, then the courts may be able to clear the title of the interest of such grantee or lessee who makes no effort for a long period of time to produce minerals from the land by holding that his non-action is sufficient evidence of intent to abandon his incorporeal interest.” (Williams, Maxwell, Meyers, Cases and Materials on the Law of Oil and Gas (1st ed. 1956); see also 1 Williams & Meyers, Oil & Gas Law, § 210.1; Smith, Methods for Facilitating the Development of Oil and Gas Interests (1964) 43 Tex.L.Rev. 129, 161; cf. Woodward, Ownership of Interests in Oil and Gas (1965) 26 Ohio St.L.J. 353, 365-366.) The property law of this state thus compels the conclusion that the perpetual profits a prendre here involved are subject to abandonment. 3. The cases which hold that a “fee interest” cannot be abandoned use the term in its possessory rather than durational sense; cases using “fee interest” in describing an incorporeal hereditament refer only to its duration and do not hold that it cannot be abandoned. We next demonstrate the fallacy in plaintiffs’ argument that, since Callahan and Dabney-Johnston describe a perpetual profit as a “fee interest,” the interest is because of its “fee” nature not subject to abandonment. We shall explain that in Callahan and Dabney-Johnston the court used the term “fee” to designate merely the duration of the estate; this designation in no way alters our conclusion that a perpetual incorporeal hereditament can be abandoned. It is true, as plaintiffs point out, that many California cases have declared that a fee simple interest in real property may not be abandoned. “And indeed, regarding the title passing by virtue of the ordinance, as a title in fee, neither abandonment or disclaimer has any application to or effect upon such title or the right to the possession following therefrom.” (Davis v. Perley (1866) 30 Cal. 630, 636; Davenport v. Turpin (1872) 43 Cal. 597, 602, overruled on other grounds, Burns v. Hiatt (1906) 149 Cal. 617, 625-626 [87 P. 196, 117 Am.St.Rep. 157] ; Ferris v. Coover (1858) 10 Cal. 589, 631 ; Hunter v. Schultz (1966) 240 Cal.App.2d 24, 28 [49 Cal.Rptr. 315] ; Kern County Land Co. v. Nighbert (1925) 75 Cal.App. 103, 106 [241 P. 915].) As we have pointed out ante, at pages 881-882, the courts have also held, however, that perpetual easements in real property are also “fee interests” yet that such interests can be abandoned. ' The explanation of the superficial disparity in the consequences of ownership of these interests in real property becomes clear when we consider that our courts have employed the term ‘ ‘ fee.’ ’ to describe two different concepts. (See Highland Realty Co. v. City of San Rafael, supra, 46 Cal.2d 669, 677 fn. 1.) In one sense the courts use “fee” to describe the totality of the possessory and corporeal rights of ownership in real property. Hence in some cases they have spoken of a fee interest as distinguished from an easement. (E.g., Southern Pac. R.R. Co. v. San Francisco Sav. Union (1905) 146 Cal. 290 [79 P. 961, 106 Am.St.Rep. 36, 2 Ann.Cas. 962, 70 L.R.A. 221] (owner of fee burdened with an easement may be entitled to award in eminent domain) ; Faus v. City of Los Angeles (1961) 195 Cal.App.2d 134 [15 Cal.Rptr. 783] (railroad took fee rather than easement for right of way and therefore owned mineral rights) ; Ocean Shore R.R. Co. v. Doelger, supra, 127 Cal.App.2d 392, 402 fn. (if right of way held in fee rather than easement it cannot be abandoned; i.e., if the railroad owns the land rather than merely the right to use the land, the right of way cannot be abandoned); see generally 6 A.L.R.3d 973.) On the other hand, the courts describe fee ownership as any estate of inheritance. (Civ. Code, §762; Burnett v. Piercy (1906) 149 Cal. 178, 190 [86 P. 603].) In In re Barlow v. Security Trust & Sav. Bank (1925) 197 Cal. 263 at p. 266 [240 P. 19], we explained, “ ‘Fee simple’ therefore merely means that the interest of a given estate is inheritable and not subject to ‘ conditions or collateral determination. ’ Nor is the inheritable quality of the estate at all affected by the nature thereof.” We quoted Blackstone’s explanation: “Taking, therefore, fee ... as a state of inheritance, it is applicable to, and may be had in any kind of hereditaments, either corporeal or incorporeal .... The dominicum or property is frequently in one man, while the appendage or service is in another. Thus Gaius may be seised as of fee of a way leading over the land, of which Titius is seised in his demesne as of fee.” (2 Blackstone, Commentaries *106,107.) The holdings in Callahan and Dabney-Johnston clearly negate the possibility that this court used the description “fee” as an indication of anything but the duration of the interests. Thus Dabney-3 ohnston speaks of a profit held in fee in contradistinction to one held for a term of years. (4 Cal.2d 637, 649.) And the thrust of Callahan is that the holder of a profit to remove oil and gas enjoys no definitive possessory ownership of these substances until they are severed from the realty and become personal property. We conclude that the rulings in the cases cited at page 23, supra, that a “fee” interest in real property cannot be abandoned are explicable only upon an analysis of the facts involved in the particular eases; in each case the court concerned itself with title to corporeal real property. Thus these cases are entirely consistent with the cases we follow here, holding that easements 1‘ in fee ’ ’ may be abandoned. To summarize, we look to the nature of the interest as well as its duration to define plaintiffs’ rights. Incorporeal interests, as distinguished from corporeal ones, may be abandoned, whatever their life, whether limited or unlimited in time, whether "fee” or a term, whether perpetual or restricted. In short, the temporal life of the hereditament does not tell us for this purpose what kind of a legal interest it is; we must classify it according to its genus, not merely its durational characteristic. 4. Principle and policy support the conclusion that plaintiffs’ interests are subject to abandonment. Although the historical rationale for the rule that certain interests in real property cannot be abandoned finds little articulation in the cases, the reason appears to be that society cannot tolerate voids in the ownership of land. (2 American Law of Property, Basements, §8.98, p. 304.) As stated by the court in Kern County Land Co. v. Nighbert, supra, 75 Cal.App. 103 at p. 108, "The title to land is not a nebulous thing; it must rest somewhere.” No such abeyance in ownership arises, however, if the owner of a perpetual profit chooses to abandon his interest. Comment (a) to section 504 of the Restatement of Property states: ‘1 That there is an ownership ready to take the benefit resulting from an abandonment of an easement is the probable explanation of the tolerance of the law toward the abandonment of such interests. In many cases, of which the ownership of land in fee is an example, an abandonment, if permitted, would result in a void in the ownership of the affected thing, the filling of which would be largely a question of chance and would probably produce grave uncertainty of title.” (Cf. 2 Pollock & Maitland, History of English Law (1895) 80.) If interests in real property can be and are abandoned, they do not become, as in the ease of personal property, the property of the first appropriator (see 1 Cal.Jur.2d, Abandonment, § 10), but instead return to the estate out of which they were carved. The abandonment of a profit a prendre, therefore, because the profit in essence is an easement, does not become subject to the void in ownership that the common law of land title sought to avoid. If a perpetual right of way or other easement is abandoned, the property interest reverts to the servient estate (Lake Merced Golf & Country Club v. Ocean Shore R.R. Co., supra, 206 Cal.App.2d 421, 438). Similarly, a perpetual right to remove oil and gas (see Civ. Code, §§ 801, 802) would ordinarily revert to the surface estate, thereby freeing that estate of its burden and permitting its owner more complete utilization and enjoyment of his property. (See Miller v. State, supra, 121 Conn. 43, 48; Mathews Slate Co. v. Advance Industrial Supply Co., supra, 185 App. Div. 74; see also Rest., Property, § 450, Note.) Commentators have noted that “The abandonment concept, when applied, frequently serves the very useful purpose of clearing title to land of mineral interest of long standing, the existence of which may impede exploration or development of the premises by reason of difficulty of ascertainment of present owners or of difficulty of obtaining the joinder of such owners.” (1 Williams & Meyers, Oil and Gas Law, §210.1, pp. 104-105, see also Smith, Methods for Facilitating the Development of Oil and Gas Lands Burdened with Outstanding Mineral Interests, supra, 43 Tex.L.Rev. 129, 129-136; Street, The Need for Legislation to Eliminate Dormant Royalty Interests (March 1963) 42 Mich. State B.J. 49; cf. Audrain, Title Insurance of Oil and Gas Leases (1956) 3 U.C.L.A. L.Rev. 523, 530.) As stated in Dabney-Johnston, “the use of different terms of description may give rise to different legal incidents . . . .” (4 Cal.2d at p. 649.) By describing rights identical to those granted to the corporations as incorporeal hereditaments our court foreordained the conclusion we now reach. Moreover, a ruling that incorporeal hereditaments of the type involved here may he abandoned tends to promote the marketability of title by facilitating the clearing of titles. To that extent it better fulfills the demands of a modern economic order. Further, it reduces the possibility of the resurrection of the ghosts of abandoned claims by which title searchers and forgotten owners collect the windfalls of accidental profit. In recognizing the freedom of an owner of an unlimited profit a prendre to abandon his interest, we realize, of course, that factual issues may determine the ownership of such interests. The establishment of title by the resolution of factual, as opposed to legal, questions, however, does not create undesirable uncertainty as to the ownership of real property, since trial courts and juries must frequently make such resolutions determinative of title. (E.g., Masterson v. Sine (1968) ante, p. 222 [65 Cal.Rptr. 545, 436 P.2d 561]; Ernie v. Trinity Lutheran Church (1959) 51 Cal.2d 702, 707-708 [336 P.2d 525] ; People v. Ocean Shore R.R., Inc., supra, 32 Cal.2d 406, 417; Williams v. Stillwell (1933) 217 Cal. 487, 493 [19 P.2d 773] ; cf. Faus v. City of Los Angeles, supra, 67 Cal.2d 350, 360-361.) In the instant case we protect the required stability of title by adhering to the rules of law governing ownership of real property. (See Abbott v. City of Los Angeles (1958) 50 Cal.2d 438, 456 [326 P.2d 484] ; Smith v. McDonald (1871) 42 Cal. 484, 487-488; Pioche v. Paul (1863) 22 Cal. 105,109-110.) Moreover, our holding leaves open no possibility that owners of valuable property rights of the type herein involved will, contrary to their desire, lose these rights. As we shall point out, abandonment hinges upon the intent of the owner to forego all future conforming uses of Ms property, and the trier of fact must find the conduct demonstrating the intent “so decisive and conclusive as to indicate a clear intent to abandon . . . .” (Smith v. Worn, supra, 93 Cal. 206, 213.) B. Evidence of abandonment: general principles. We now consider the propriety of the trial court’s finding that all plaintiffs or their predecessors had abandoned their interests in the fugacious minerals underlying section 31. We initially point out that the dominant owner cannot extinguish a profit a prendre by abandonment without the concurrence of two elements, his nonuser and his intent to abandon. We then explain that the trier of fact, before decreeing an abandonment, must find that the owner’s conduct clearly and convincingly demonstrates the necessary intent. Following the appropriate precedents, we hold that the evidence does not sufficiently support the trial court’s finding that the Gerhard, Solomon, and Mettler plaintiffs had abandoned their interests; we explain that under the circumstances the trial court could not reasonably infer from their conduct in not making use of their property that they intended to abandon it. We affirm the trial court’s finding as to the Weber plaintiffs; additional circumstances make reasonable the trial court’s inference. We have pointed out, supra, that we cannot differentiate profits a prendre and easements in terms of the legal consequences stemming from ownership. Accordingly, in determining whether defendants have established an abandonment, we may with propriety consider the cases that discuss abandonment of perpetual easements created by grant. “ ‘As a general rule, in order to constitute an abandonment of an easement . . . there must be a nonuser accompanied by unequivocal and decisive acts on the part of the [dominant tenant], clearly showing an intention to abandon.’ ” (People v. Southern Pac. Co., supra, 172 Cal. 692, 700.) As other cases point out, however, the owner’s nonuser itself may under some circumstances constitute such an act. “ Where nonuser is evidence of an abandonment of a right, the question is one of intention, depending on the circumstances . . . .” (Smith v. Worn, supra, 93 Cal. 206, 213.) “And while nonuser alone does not extinguish the easement, a long continued nonuser is some evidence of an intent to abandon.” (Home Real Estate Co. v. Los Angeles Pac. Co., supra, 163 Cal. 710, 714 [126 P. 972] ; see, e.g., Lake Merced Golf & Country Club v. Ocean Shore R.R. Co., supra, 206 Cal.App.2d 421, 436-437; Ocean Shore R.R. Co. v. Doelger, supra, 179 Cal.App.2d 222, 232; Flanagan v. San Marcos Silk Co., supra, 106 Cal.App.2d 458, 463.) Although “ [t]he acts of the owner of the dominant tenement, to prevent him from [enjoying] an easement acquired by grant, must be of a character so decisive and conclusive as to indicate a clear intent to abandon the easement” (Smith v. Worn, supra, 93 Cal. 206, 213), the question of abandonment is one for the trier of fact. (Smith v. Worn, supra, 93 Cal. 206, 213.) “It is no doubt true, as claimed by appellant, that mere nonuser, not accompanied by an intent to abandon, will not divest the right of the railroad company to the easement. [Citations.) But in this class of cases as in others, the intention with which an act is done is a question of fact, to be determined by the trial court or jury from a consideration of the conduct of the party and the surrounding circumstances. Where the evidence is such that a finding either way might reasonably be made, the conclusion of the trial court must be upheld under the familiar rule protecting from review on appeal findings based on conflicting evidence.” (Home Real Estate Co. v. Los Angeles Pac. Co. supra, 163 Cal. 710, 714.) 1. Evidence of abandonment: plaintiffs Gerhard, Solomon, and Mettler. Turning now to the evidence before the trial court on the issue of abandonment, we first examine its sufficiency as to plaintiffs Gerhard, Solomon, and Mettler, who claim as successors of Ashurst stockholders. As to these plaintiffs the trial court ruled that they and their predecessors did not abandon their stock but later abandoned the interests in real property to which they succeeded after Ashurst forfeited its charter. The court found that plaintiffs’ predecessors (other than Brandt) defaulted in the quiet title action which Brandt brought in 1917 (action 1870) : 11 they failed to include their interests in the estates of those who became deceased, . . . they never set foot on the surface of Section 31, . . . they never attempted to search for oil nor to lease to others to drill for oil, nor to inquire of the Frusetta-Cornwell-Irvine defendants concerning this property, nor to demand of them some interest in the proceeds of oil leases, nor to have their fractional shares set apart and assessed by San Benito County for tax purposes. Prior to the present controversy, no decrees of distribution in the estates of any of plaintiffs’ predecessors had been recorded in San Benito County. ’ ’ Several California eases which have upheld a trial court’s determination that a dominant tenant has abandoned an easement created by grant have found sufficient evidence of the requisite intent by evaluating the implications of nonuser in terms of “economic exigencies” and “external realities.” (Ocean Shore R.R. Co. v. Doelger, supra, 179 Cal.App.2d 222, 232; People v. Ocean Shore R.R., Inc., supra, 32 Cal.2d 406, 419.) Thus, in the Ocean Shore cases, the courts sustained findings of abandonment when the evidence showed that the restoration of service would be prohibitively expensive and that effective competition with other carriers was realistically impossible. (Lake Merced Golf & Country Club v. Ocean Shore R.R. Co., supra, 206 Cal.App.2d 421; Ocean Shore R.R. Co. v. Doelger, supra, 179 Cal.App.2d 222; cf. People v. Ocean Shore R.R., Inc., supra, 32 Cal.2d 406, 419.) In Home Real Estate Co. v. Los Angeles Pac. Co., supra, 163 Cal. 710, the railroad had constructed and operated on a track paralleling the unused track on the right of way; the railroad’s superintendent testified that “ 'as there were no passengers to travel on [the old line], ... we quit.’” In Flanagan v. San Marcos Silk Co., supra, 106 Cal.App.2d 458, the defendant’s pipeline, for which it had an easement to carry water, would have needed costly repair work to become serviceable again, and the company had developed alternate sources of supply. Other California cases point out that the dominant tenant’s nonuse does not tend to demonstrate the requisite intent merely because the activation of the easement would produce no immediate benefit sufficient to justify the necessary expense. As we pointed out in Faus v. City of Los Angeles, supra, 67 Cal.2d 350 at p. 363, “the holder must . . . manifest an intent to forswear all future conforming uses of the easement.” (Italics added.) Thus in People v. Southern Pac. Co., supra, 172 Cal. 692, we rejected the trial court’s finding that the railroad had abandoned its easement: ‘ ‘ There is no proof that the needs of commerce during this period were such that . . . the existing or probable immediate future traffic would have justified the cost of building such tracks . . . .” (P. 699.) In Parker v. Swett (1919) 40 Cal.App. 68 [180 P. 351], the court reversed the judgment for defendants : “The evidence of plaintiff’s predecessor in interest is to the effect that he never exercised his right to lay the pipe for the reason that he did not require the water during his ownership of the ranch and the installation of a pipe-line was quite expensive.” (P.74.) We have pointed out supra that “While nonuse alone does not establish intent, the court may consider the length of the nonuse in ascertaining the existence of such intent.” (Ocean Shore R.R. Co. v. Doelger, supra, 179 Cal.App.2d 222, 232.) We must determine whether the trial court could reasonably find the necessary intent on the basis of plaintiffs’ 47 years of nonuser, their apparent lack of concern with their interests, and their failure to give any visible indication of intent to make future use of the property. Abrams and Brandt purchased the Syncline Ranch in 1905, during an 11 oil boom ’ ’ in the area. They organized Ashurst in order to obtain financial backing for the contemplated exploration for, and production of, oil and gas. After the corporation’s dissolution in 1915, however, the oil interests were no longer owned and managed by a unified corporate structure; instead these interests embraced 148 owners, many of whom, as evidenced by the judgment roll in action 1870, could not be located. Any one of these owners individually could have entered upon section 31 and explored for oil and gas. (Callahan v. Martin, supra, 3 Cal.2d 110, 125-126.) In doing so, however, he would, if unsuccessful, have been compelled to bear the entire expense and risk of the operations. (See Little v. Mountain View Dairies, Inc. (1950) 35 Cal.2d 232, 234 [217 P.2d 416] ; cf. McCord v. Oakland Quicksilver Min. Co. (1883) 64 Cal. 134, 149-150 [27 P. 863, 49 Am.Rep. 686].) If he had succeeded in his endeavor, he could not have excluded from section 31 other cotenants who had desired to drill (DabneyJohnston Oil Corp. v. Walden, supra, 4 Cal.2d 637, 655; Callahan v. Martin, supra, 3 Cal.2d 110, 125-126), and, as to the remaining cotenants, he would have been required to render an accounting for the profits (Dabney-Johnston Oil Corp. v. Walden, supra, 4 Cal.2d 637, 655-657). An extended nonuser, when considered in light of these “economic exigencies” and “external realities” (Ocean Shore R.R. Co. v. Doelger, supra, 179 Cal.App.2d 222, 232) cannot by itself support the trial court’s finding of intent to abandon. Although the acquisition of such an interest in oil and gas may be entirely speculative and the owner may well intend to forsake his interest if the “oil boom” which induced his purchase collapses, plaintiffs and their predeeessors, incurring no significant detriment by retaining their interests, might well have contemplated that the property might again become valuable because of the efforts of others. In order to protect the owner of an unlimited profit a prendre or other incorporeal hereditament against “involuntary” abandonment under circumstances in which conflicting inferences may be drawn from his nonuser we hold that the trial court must find either that the owner’s future use of the right could result only from a palpably unsound business judgment or that the owner has given a further indication of his intent to abandon. Applying this principle, derived from the cases cited supra, to the instant situation we find no substantial evidence to support the finding that plaintiffs Gerhard, Solomon, and Mettler abandoned their interests in section 31. 2. Evidence of Abandonment: Weber Plaintiffs As to the Weber plaintiffs, we uphold the trial court’s finding of abandonment. Before discussing the sufficiency of the evidence of abandonment, however, we dispose of plaintiffs’ contention that the judgment in Brandt’s quiet title suit of 1917 renders the issue of abandonment res judicata. (Action 1870.) In his action to quiet title to the Syncline Ranch, Brandt named as defendants the stockholders in several corporations, including those in Ashurst and COP when those corporations forfeited their charters. All of these defendants defaulted, except that a purported trustee for COP filed an answer. The judgment stated that the named shareholders became coowners of the interests held by the corporations at the times the charters were forfeited, Even if we assume that the judgment in action 1870 conclusively determined that the shareholders had not abandoned their interests on the judgment date, the judgment would not preclude a finding of abandonment at a later date. Moreover, we may consider the actions and circumstances preceding the prior decree as well as subsequent facts in determining whether plaintiffs have abandoned their interests. (People v. Ocean Shore R.R., Inc., supra, 32 Cal.2d 406, 418-419; Lake Merced Golf & Country Club v. Ocean Shore R.R. Co., supra, 206 Cal.App.2d 421, 434-435; Ocean Shore R.R. Co. v. Doelger, supra, 179 Cal.App.2d 222, 234.) “The trial court examined the totality of facts and circumstances not to disprove the findings in the previous case, but to test the present force and validity of the intent in the light of its previous history.” (Ocean Shore R.R. Co. v. Doelger, supra, 179 Cal.App.2d 222, 234.) The trial court found that the Weber plaintiffs are the successors of the children of Charles M. Weber, who died in 1912. In 1914 the probate court entered its order and decree finally closing Weber's estate; it recited: “The following personal property belonging to said estate and inventoried and appraised therein as of no value . . . has been tendered and offered for delivery and distribution to said distributees [his children: Helen M. Kennedy and Charles M. Weber] but the receipt and acceptance of the same have been refused by the distributees[] on account of said stocks being worthless and of no value, to wit [33,527 shares of Ashurst and 264,40b shares of COP].” In rejecting the stock the heirs thereby gave a positive indication of an intent to renounce their rights (see Lake Merced Golf & County Club v. Ocean Shore R.R. Co., supra, 206 Cal.App.2d 421, 435, 438; Ocean Shore R.R. Co. v. Doelger, supra, 179 Cal.App.2d 222, 228; Rest., Property, § 504, com. e.) Even if we should conclude that these plaintiffs did not in fact abandon their interests by specifically rejecting the shares of Ashurst and COP, we cannot ignore the trial court’s finding of corroboration of an intent to abandon by their subsequent conduct. Like the predecessors of plaintiffs in the other actions, they made no use whatsoever of the property for an extended period of time that lengthened into almost a half century. We cannot hold unreasonable the trial court’s determination that in light of their earlier decision the nonuser indicates and confirms their intent to abandon. A further factor demonstrating such intent as to the interests conveyed to COP was that the interests continued to be subject to the COP mortgage, which, the court in action 1870 found, constituted an extant lien on the corporate assets. (Cf. 13 Cal. Jur.2d, Cotenancy, §§ 29, 30.) Our holding that the trial court properly found that the Weber plaintiffs abandoned their interests in the oil and gas and other fugacious minerals underlying section 31 does not completely dispose of that appeal. The grants to Ashurst and COP included Abrams’ and Brandt’s interest in certain specified hydrocarbon substances other than oil and gas. Although most of these substances are liquid or semiliquid in their natural state, one such substance possesses nonfugacious qualities. We have pointed out, supra, that the partnership ’s deed purports to convey a complete possessory estate in the specified minerals, hut, because of the fugacious nature of oil and gas, our courts could not give effect to a transfer of the latter substances as corporeal real property but would instead treat the deed as conveying ownership of an unlimited profit a prendre in the fugacious minerals. As to any nonfugacious minerals underlying section 31, however, Abrams and Brandt had title to them in place and therefore could convey them as corporeal real property. We have concluded, however, that the grantors, in conveying their rights in the enumerated minerals in a single deed to each corporation, did not intend to convey two different types of estate in the same instrument. The grantors had the power and right to convey a. profit a prendre in the nonfugacious minerals. (See Civ. Code, § 802; see also the discussion in Miller v. State, supra, 121 Conn. 43, 46-48.) In making the conveyance they were primarily concerned with transferring the oil and gas rights to the corporations, as is evidenced by the then extant oil boom in the area and by the names of the corporations (Ashurst Oil, Land and Development Company and California Oil Products Compaq’). In treating the incidental conveyance of the asphalt as a conveyance of a profit a prendre we are in accord with Callahan v. Martin, supra, 3 Cal.2d 110, and Dabney-Johnston Oil Corp. v. Walden, supra, 4 Cal.2d 637, in which the interests disputed were rights in oil, gas, and other hydrocarbons; yet this court did not distinguish, or even mention, nonfugacious hydrocarbons in its analysis of the nature of the interests in question. 2. Adverse Possession The trial court concluded that the Frusetta-Cornwell defendants had acquired title to section 31 “in fee” by adverse possession. In support of that conclusion the court found that for over 20 years prior to the instigation of this litigation defendants and their predecessors had improved the Syncline Ranch, including section 31, by fencing it and conducting cattle operations on it; they had excluded trespassers from the property; they had paid all taxes assessed against section 31, although the mineral estate was not separately assessed. The court also found that for more than five years before the commencement of this action defendants had exercised dominion over the section 31 oil and gas rights by negotiating leases and receiving rentals. These acts, the court determined, were so open and notoriously adverse to the interests of plaintiffs’ predecessors as to effectuate an ouster and mature a title in defendants to the entire fee in section 31, including the interests now claimed by plaintiffs. Plaintiffs contend that no sufficient evidence supports the trial court’s finding. They point out that defendants engaged in no visible activity adverse to plaintiffs’ claimed interests until 1956, when oil was discovered on section 31. They argue that defendants’ recording of several instruments in which they claimed to own without reservation the entire estate in section 31 and their failure to account to plaintiffs for the rentals received from the leases did not give notice to plaintiffs that their alleged cotenants were claiming adversely to them. We shall explain that the cases hold that the owner’s possession of the surface does not necessarily earn property rights, previously conveyed to another, in the oil and gas underlying the surface. We point out that defendants engaged in no subsurface activity sufficient to acquire a prescriptive title to the interest previously conveyed to the corporations; we further point out that defendants’ surface activities were not adverse to plaintiffs’ enjoyment of their interests. Although the courts generally hold that adverse possession of the surface extends to the underlying mineral estate (see cases cited, 35 A.L.R.2d 124, 129-138; 1 Williams & Meyers, Oil & Gas Law, § 224, p. 337; 1 Kuntz, Oil and Gas, §10.2; 1A Summers, Oil and Gas, § 138, p. 306), continued possession of the surface, following a conveyance of the oil and gas rights apart from the surface, does not establish the possessor’s rights against the legal owner. (See cases cited, 35 A.L.R.2d 124, 154-165; 1 Williams & Meyers, op. cit. supra, §224, p. 338; 1A Summers, Oil and Gas, § 138, pp. 307-312.) The reason for the rule lies in the fact that the true owner of a mineral interest would not be alerted to a hostile claim on the part of an occupant who takes no steps to penetrate the surface. (See Smith v. Pittston Co. (1962) 203 Va. 408, 412 [124 S.E.2d 1]; 1 Williams & Meyers, op.cit. supra, § 224.1, pp. 340-341.) In Foss v. Central Pac. R.R. Co. (1935) 9 Cal.App.2d 117 [49 P.2d 292], the grantor had deeded the land to plaintiffs’ predecessors, reserving to himself a part of apparently nonfugacious mineral rights and necessary easements for mining. Entering the land under a decree of distribution which did not mention the reserved mineral rights, plaintiffs “paid the taxes on the land, made improvements, used a small portion for a family cemetery, granted a right of way for a county road, enclosed the land with fences and excluded trespassers, and leased the property at times for pasturage and grazing. ’ ’ (P. 119.) In Foss the court held: “Where the title to the mineral rights has been severed from the title to the surface, possession of the surface by its owner is not adverse to the owner of the mineral below it. The surface owner cannot acquire title to the minerals by adverse possession based on his exclusive and continued occupancy of the surface alone [citations]. The act of the surface owner in paying the taxes on the land containing the minerals does not constitute adverse possession of the minerals [citation]. The fact that the owner of the minerals does not pay the taxes on the minerals is not in derogation of his claim to their ownership, where the minerals are not separately assessed, and the taxes charged against the land are not increased by reason of the existence of the minerals [citation].... None of the various acts of possession and ownership by the appellants has been adverse to the rights of respondents to the subsurface minerals. The establishment of the family cemetery is urged as a strong point, but there is no assertion of rights to the minerals in this act, and there is no showing that it would ever interfere with mining operations.” (Pp. 120-121.) Thus the courts have indicated that mere possession and ownership of the surface, in the absence of visible activity sufficient to impart to the true owner notice of an adverse claim, does not give rise to adverse title to rights in the underlying minerals. Indeed some courts have taken the extreme position that, following a conveyance of the mineral rights, subsurface activity by the surface owner on a part of a tract will not give title by constructive adverse possession to the mineral rights appurtenant to the entire tract (e.g., Sanford v. Alabama Power Co., supra, 256 Ala. 280, 289-290; Piney Oil & Gas Co. v. Scott, supra, 258 Ky. 51, 65), Other courts have held that the development of part of the subsurface estate under color of title to the entire tract will mature a prescriptive title to the entire mineral estate (e.g., Vance v. Guy (1943) 223 N.C. 409 [27 S.E.2d 117] (three or four small mines on 375-aere tract); Diederich v. Ware (Ky. App. 1956) 288 S.W.2d 643 (two producing wells on 56-acre tract)). Applying these rules to the instant case we conclude that no evidence supports the trial court’s finding that defendants acquired a prescriptive title to the oil and gas rights. Defendants’ lessees did no drilling on section 31 until shortly before the commencement of the present actions. (See Graybiel v. Burke (1954) 124 Cal.App.2d 255, 263-264 [268 P.2d 551].) Defendants’ execution and recording of leases does not by itself constitute the actual and visible physical enjoyment of the subject rights essential to place the true owner on notice of an adverse claim. (See West v. Evans (1946) 29 Cal.2d 414, 417, 418 [175 P.2d 219] ; cf. Lundy v. Lakin (1950) 96 Cal.App.2d 221, 223 [215 P.2d 61] ; see also Piney Oil & Gas Co. v. Scott, supra, 258 Ky. 51, 66-67; Viersen v. Boettcher (Okla. 1963) 387 P.2d 133,138.) We recognize that defendants’ lessee Hess drilled a dry hole on the Syncline Ranch just outside of section 31 in 1951, but, even if this single action would suffice as a continuous and notorious user for the requisite period, defendants cannot on this basis establish title under the doctrine of constructive adverse possession. (See Code Civ. Proe., §§ 322, 323.) Although defendants held color of title to a complete interest in the oil and gas underlying the Syncline Ranch including section 31 their lessee’s activity did not intrude upon the interests now claimed hy plaintiffs. The California cases hold that a person in actual possession of only a part of the land to which he has color of title cannot establish ownership of the entire tract by adverse possession unless his actual possession infringes upon the presumptive possession of the true owners of the land. Thus in Wheatley v. San Pedro etc. R.R. Co. (1915) 169 Cal. 505, 516 [147 P. 135], defendant obtained a deed to property, but his grantor had title only to a part of the area described. Defendant’s actual possession of that portion to which he had good title, we held, could not give him title by constructive adverse possession to the remaining portion. (See also Kimball v. Stormer (1884) 65 Cal. 116, 120 [3 P. 408] ; cf. Lundy v. Lakin, supra, 96 Cal. App.2d 221, 223.) Defendants attempt to sustain the trial court’s finding by pointing out that because California regards the oil and gas interests here in dispute as profits a prendre or incorporeal hereditaments, the servient owner may extinguish such servitudes by acts other than exploring or drilling for the substances himself. “In a non-ownership state, where the grantee ... of oil and gas rights acquires only the grantor’s . . . right to drill and appropriate, a right in the nature of a profit a prendre, an incorporeal hereditament, ... it would seem, although there is practically no authority, that excluding the grantee . . . would be such an interference with the essence of the right that the statute would begin to run, and the same conclusion would be reached if there were any interference with such right as would give an action to the grantee . ...” (2 American Law of Property, § 10.7, p. 523; see 1 Kuntz, op. cit. supra, § 10.4, pp. 218-219; 1 Williams & Meyers, op. cit. supra, § 224.4, pp. 359-360; cf. Nevada Irr. Dist. v. Keystone Copper Corp., supra, 224 Cal.App.2d 523, 532.) We find no evidence, however, that could support a finding that the profit was ‘ ‘ extinguished by the user of the servient tenement in a manner adverse to the exercise of the [incorporeal hereditament], for the period required to give title to land by adverse possession.” (Glatts v. Henson (1948) 31 Cal.2d 368, 371 [188 P.2d 745] (easement).) We find no exclusion of the grantee that would be such an interference with the essence of the right as to start the running of the statute. To extinguish an easement by adverse user the use “must either interfere with a use under the easement or have such an appearance of permanency as to create a risk of the development of doubt as to the continued existence of the easement.” (2 American Law of Property, § 8.102, p. 308.) Moreover, “ [a]n easement cannot be acquired or extinguished by adverse use unless the party whose rights are affected thereby has knowledge of the adverse nature of such use. This knowledge may be either actual or constructive, resulting from notice either express or implied.” (Clark v. Redlich (1957) 147 Cal.App.2d 500, 508 [305 P.2d 239].) The facts of the instant case bear no resemblance to those situations in which the servient owner has successfully extinguished an easement by obstructing a specifically defined right of way for the prescriptive period. (Glatts v. Henson, supra, 31 Cal.2d 368; Ross v. Lawrence (1963) 219 Cal.App. 2d 229 [33 Cal.Rptr. 135].) If defendants had covered the surface of section 31 with permanent improvements, we would not disturb a finding that the user was adverse to the development of oil and gas. Here, however, defendants’ fencing of the Syneline Ranch and their use of the surface of section 31 for cattle grazing was not inconsistent with plaintiffs’ alleged right to enter upon the tract and explore for oil. (See Barker v. Campbell-Ratcliff Land Co. (1917) 64 Okla. 249, 251 [1