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'Waucoba Wews Sponsored by The BIshop Museum & HIstorIcal SocIety, BIshop, Ca. 9.351 Lt VOLUME IIIFounded and Edited by Enid A. larson, Box 265 81g Pine Ca 9.351.3 SUPPLEMENT No. 2 lS-H.Subscrtption:

B Four 9" ton s anped set f-addr~ssed envejope~ 4 issues per y~ar

'. Notes on Inyo County Grasses - 5

The Fescue Grasses (Festuca) in the Inyo Sierra By John Thomas Howell

I. Perennials. Festuca subgenus Festuca

F. ovin~ L. var.b:evifolia (R. Brown) Watson. Alpine Fescue. Rather common ~nd widespread In rocky soil and on rocky slopes from subalpine forests to arctiC fell-fields, 10,200 to 12,200 ft. and probably higher. It has been collected at 13,400 ft. in Fresno Co.--F. brachyphylla Schultes.

F. prate~si7 Hudson. Meadow Fescue. To be reported in the Inyo-Sierra only from tra11s7de near Lake Sabrina at 9600 ft. To be expected in meadows where seeded to 1mprove forage. Native of Europe.

F. rubra L. Red Fescue. Mosquito Flat on Rock Creek, 10,300 ft.

2. Annuals. Festuca subgenus Vulpia

F. Grayi (Abrams) Piper. West of Independence at 5000 ft.; also in Alabama Hills.

F. megalura Nutt. Foothills south of Bishop; Whitney Portal Road at 7700 ft. Introduced from the Mediterranean region.

F. pacifica Piper. Onion Valley Road at 6800 ft.; also in Alabama Hills.

Notes on Inyo County Grasses - 6 The Brome Grasses (Bromus) in the Inyo Sierra

By John Thomas Howell

B. carinatus H.& A. (including B. marginatus Nees). Meadows, open woods, disturbed areas, widespread, 7000 to 11,000 ft.

B. ciliatus L. Wet or moist ground in Big Pine Lakes area 9-10,000 ft.

B. diandrus Roth. (B. rigidus of Calif. references.) Ripgut Grass. Rare Old World grass in disturbed ground as at Carrol Creek and on Olancha Pass Trail.

B. inermis Leysser. To be expected along roads and trails where intro­duced for erosion control or in meadows to improve pasture.

B. mollis L. Known in 19 counties in the Sierra but no Inyo Co. record has been seen! This Old World grass must be there too!

B. Porteri (Coulter) Nash. Dry gravelly slopes and flats, rather common in vicinity of Whitney Portal; ascending to 11,000 ft. in Rock Creek Lake Basin.

B. rubens L. Red Brome. Dry disturbed soil along roads and trails, 4000 to 7700 ft. Introduced from the Old World.

B. Suksdorfii Vasey. In moist brushy or wooded places. as at 10,000 ft. above Lake Sabrina.

B. tectorum L. Downy Chess. Common and widespread in both natural and disturbed areas, up to 11,000 ft. in Rock Creek Lake Basin; both the typical form and var. glabratus Spenner. Native in the Old World.

B. Trinii E. Desvaux. Along the base of the Sierra as in Nine-Mile Canyon, on Richter Creek wash, in Alabama Hills, and near Bishop. Native of Chile.

B. unioloides Kunth. Res~e Grass. Spontaneous about corrals and along roads and trails, 5500 ft. (Carrol Creek) to 9000 ft. (Olancha Pass Trail). Native in South America. In Calif. this species has been called B. catharticus, Haenk.~~us, and Willdenowii.

COMMENTS ON "WINGLESSNESS" IN PINES: Morphology and Evolution

The quotation which appears in Waucoba News, Winter 1979, on the role of the Clark's Nutcracker (Nucifraga columbiana) as-a-dispersal agent for whitebark (Pinus albicaulis) and limber pine (P. flexilis) comes from a letter sent to the editor, Ms. Enid Larson. Bruce Pavlik's comments on this quotation in Waucoba News, Spring. 1979, provide an opportunity for me to elaborate. ---­

The structure referred to as the "wing" of a p~ne seed is a membranous tissue (spermoderm) attached to the seed coat (testa) of a pine seed. Both the seed coat and wing are derived from the integument of the scale of the female cone (megasporangiate strobilus) in which the seed is formed (Mirov, 1967, The Genus Pinus, Ronald Press). Seeds which are shed from cones with seed wings intact may be carried by wind or local air currents some distance from the parent tree. The distance of dispersal probably varies with seed weight, tree height, and wind speed (Baker, 1950, Principles of Silviculture, McGraw-Hill). -­

Of the approximately 105spedesofpines, a~b()ut 24 have "lost" functional seed wings (pers. communication, R. M. Lanner, Utah State University). These pines are generally termed "wingless" and, in most cases, depend on dispersal agents other than wind. In "wingless" pines the seed wings are much reduced in size and/or adhere to the cone scale rather than the seed. Contrary to the statement of van der Pijl' in his well-known book (1969, Principles of Dispersal in Higher Plants, Springer-Verlag), there is much evidence to show thatwinged steedS-are the primitive condition and "wing­less" seeds the derived. For example, within the "wingless" Cembrae pines (classifi­tion according to Critchfield and Litt~e, 1966, geographic Di~tr~butio~ of the P~n,s. of the World, U.S.D.A.), we see a cont~nuum of w~ng character~st~cs: 1n P. kora1ens1s the-r,ull-sized seed wing adheres to the cone scale, in P. cembra the seed-wing is re­duced in size and adheres to the cone scale, in P. albicaulis the seed wing is essen­tially gone (Shaw, 1914, in Mirov, 1967, op cit)~

Mr. Pavlik reports collecting whitebark pine cones bearing seeds with reduced wings at Sonora Pass (Waucoba News, Spring 1979). I assume he waS referring to wing remnants. I collected P. albiCiUfis cones from Mammoth Mountain in 1975 and 1976; and, attached to the scales were tiny remnants of seed wings which varied somewhat in size from cone to cone. Small wing remnants in P. albicaulis cones also were noted by Sudworth (1908, Forest Trees of of the Pacific Slope, U.S.D.A.). Variation in the size of wing remnants is not unexpected SInce so many cone and seed characteristics are poly­morphic within species of the genus Pinus. However, the presence of remnants does not detract from the point that the seed wings are essentially "lost", i.e. can no longer medi-ate'W'ind dispersal in whitebark pine. .ApP<i:",,4ii!AAJ.y.~.,;~~· situation is similar--small wing remnants adhere to the tone (Shaw, 1914, in Mirov, 1967, op cit)--as is also the case for P. flexilis and the closely related southwestern white pine (P. strobiformis).

We can only speculate on the-steps involved in the evolution of "wingless" seeds, although some evidence comes from the limber pine complex (i.e. P. flexilis, P. strobi­formis, and P. ayacahuite), where such evolution appears in progress (pers. comm., R. M. Lanner). Although a variety of factors were probably involved in the evolution of "wing­less" pines from ancestral "winged" forms , we can focus on the role of seed-storing birds of the family Corvidae, such as the nutcracker. Nutcrackers and other corvids readily use "winged" as well as "wingless" pine seeds as a food source (Tomback, 1977, The Living Bird, p. 123-161, and references therein). However, nutcrackers and other corvids will shake off or break off seed wings before eating a seed or placing the seed in their throat pouches. Consequently for corvids, harvesting winged seeds is a less efficient process than harvesting wingless seeds (see extraction rate data in Tomback, 1977). This difference in efficiency may be· especially important when nutcrackers and other corvids are harvesting large quantities of seed for storage purposes.

If wing adherance were present at a low frequency in an ancestral pine, the spread of this trait might result from discrimination by corvids. In other words, the birds would preferentially harvest and store seeds--and thus disperse seeds--from trees with adhering seed wings, because the efficiency of their foraging would be increased.

On the other hand, reduction of wing size probably resulted from a combination of factors. When corvids became the principal dispersal agents, wing size was no longer maintained by natural selection. As in other kinds of vestigial organs, lack of selec­tion pressure usually results in the hypotrophy of the structure. Energetic considera­tions are valid here, since biological systems are essentially conservative in a number of respects. Prevention of dispersal by wind in favor of dispersal by corvids was a second possible factor favoring seed wing size reduction. (Benefits of corvid dispersal are considered in a manuscript in preparation, Tomback, 1979.) Seeds which were not blown out of coneS stood a better chance of being corvid-di'persed. In addition, nut­crackers may have preferred handling cones and seeds with small seed wing remnants, again perhaps because of efficiency.

Whether or not "winglessness" evolves in a species of pine under selection pressure from corvid-mediated seed dispersal probably depends on a variety of preadaptations in the pine. For example, an important consideration is the potential of the pine for seed germination and seedling survival in the sites used by corvids for seed storage, and whether corvid-mediated dispersal will lead to a greater reproductive success than wind­mediated dispersal. In the Sierra Nevada the Clark's Nutcracker is an important factor in the subalpine ecosystem as a consequence of its relationship with P. albicaulis and P. flexilis. I look forward to continuing my work on the interactions of the Clark's Nut-­cracker and these pines.

--Diana F. Tomback