138 SALICACE^. 



at first quite conceal the body of the ament; stamens 1 or 2; bracts 

 spatulate, rounded at apex, yellowish or pallid; pistillate aments very 

 slender as compared with the last species, 2 in. long or in fruit 3 in. 

 long; bracts somewhat shorter and broader than in the staminate, 

 more acute; stigmas short-oblong, entire or nearly so. 



Along stream banks, from Santa Barbara to Wright's, Santa Cruz 

 Mountains; Lagunitas Creek, Marin Co. and northward. Mar. 



2. POPULUS L. PoPLAB. 

 Trees with scaly buds and caducous stipules; leaves long-petioled , 

 broad. Aments (catkins) appearing before the leaves, in ours pendu- 

 lous, sessile or nearly so; bracts fimbriate or lacerate, caducous. 

 Stamens Inserted on the surface of a concave, often oblique, disk. 

 Ovary more or less surrounded by a disk; style short, stigmas 2 to 4, 

 narrow and elongated or in ours conspicuously dilated. Capsule 2 to 

 4-valved. Coma of the seeds usually very long and conspicuous. 

 (Classical Latin name of the Poplar.) 



Leaves deltoid-orbicular, broader than long, green or yellowish-green, alike on 



both faces 1. P. Fremonti. 



Leaves longer than broad, ovate, green above, rusty or silvery beneath . . . . 



2. P. iHchocarpa, 



1. P. Fremonti Wats. Common Cottohwood. Tree 30 to 50 

 ft. high with a broad crown of wide-spreading branches; young twigs 

 straw-colored; leaves deltoid-orbicular, broader than long, the margin 

 crenate or sinuate crenate but entire at the abruptly short-pointed (or 

 rarely obtuse) apex and at the truncate or subcordate base, 2 to 4 in. 

 broad, IJ to 3 in. long, green or yellowish-green on both surfaces; 

 staminate aments 1 to IJ in. long, densely flowered, stamens on an 

 entire disk, 60 to 80, with dark red anthers; pistillate aments 2 in. long, 

 loosely flowered; ovary crowned with three roundish stigmas and sur- 

 rounded at base by a membranaceous disk which is persistent under the 

 capsule; fruiting aments 4 or 5 in. long; capsules on pedicels 2 lines 

 long, ovate, obtuse, minutely rough-tuberculate or transversely ridged, 

 4 to 5 lines long, 3 or 4-valved; seeds 1 line long, with an abundance of 

 long white hairs which cover the mature ament with a dense soft 

 cottony mass. 



Common in interior valleys, along creeks and rivers, throughout 

 California; not seen in the seaward or middle North Coast Ranges 

 within our limits. 



2. P. trichocarpa Hook. Black Cottonwood. Tree 20 to 80 

 ft. high with a rather broad head of upright branches; leaves ovate or 

 broadly oblong-ovate, round at base, acute at apex, serrulate, dark- 

 green and shining above, rusty or silvery beneath, 2 to 3J in. long on 

 petioles 1 or IJ in. long or less; staminate aments 1 to IJ in. long, 

 stamens on an oblique disk 40 to 60, with light-purple anthers; 

 pistillate aments loosely flowered, 2 J to 3 in. long; ovary crowned by 

 three dilated deeply lobed stigmas; fruiting ament 4 to 5 in. long; 

 capsule nearly sessile, 3-valved; seed 1 line long, with long lustrous 

 white hairs. 



