20. VITIS ARIZONICA, Engelmann, in Am. Nat. 2, pp. 321 and 268. (See Plate XXX.) 



Sjmonyms : 



V. cBstivalis, var. Gray, PI Wright 2, 27. 

 V. (Estivalis, Torrey, Pac. R. Rep. 7, 9. 



Plant: In specimens from Western Texas on the Rio Grande and Arizona, weak, much 

 branched, like V. rupestris, little climbing, slender, tapering rapidly, angled when young, and 

 cottony, remaining so first season, obscurely striated, — still less than in V. rupestris. Growing 

 tips sUghtly or not at all enveloped in expanding leaves. The gray cottony hairs upon the 

 leaves give the entire plant a dull ashy appearance. 



Roots: Slender, wiry, little transversely wrinkled, in one year seedlings axial, tapering from 

 collar downward. 



Wood : Mature bark dark, almost black, cracks after first year and separates into thin, fragile, 

 non- fibrous plates; mature wood very dense and hard; nodes scarcely at all enlarged, mostly 

 straight, diaphragm 1/12', — about the same as in V. rupestris, — biconcave; buds small, but large 

 proportionally to branch, globose, whitish, woolly both when dormant and expanding; tendrils 

 mostly once or twice forked, small, about the same length as leaves, cottony, deciduous first year 

 if not clinging to some support, then holds weakly; internodes very short, 3/4' to 2J^' long. 



Leaves: Stipules 1/12' to 1/16' long, thinly cottony. Petiole half as long as the blade is 

 wide, cylindrical, distinctly or faintly grooved on upper side, faintly striate, usually pubescent 

 and cottony; like the tendrils and young wood, dark red when young appearing dull under the 

 cotton, set at acute or right angle with blade; blade IJ^' to 4' wide by same in length; generally 

 beautifully and regularly cordate, sometimes slightly acute lobed ; basal sinus usually quite broad, 

 at insertion of petiole, in the more cordate forms, sinus n shaped with limbs partly closing around 

 it; margin curving toward back of leaf , causing upper surface to be somewhat convex; rarely lobed, 

 teeth broad, usually shallow, acute to rarely right angled, mostly convex, sometimes straight on 

 margin, with a very acute or mucronate point; margins of teeth pubescent; venation from the 

 generally 6, rarely 5 or 7, pairs of nearly opposite ribs, with httle or no prominence; usually 

 pubescent along the ribs and with pubescent tufts in forks of ribs ; surfaces generally covered with 

 gray cottony hairs, giving a dull, ashy appearance; color dark dull green; texture very dense in its 

 native, dry regions; thin and fragile at Denison, Texas. Leaves of seedling first year, entire. 



Cluster: Similar to that of V. vulpina, but smaller, peduncle and rachis cottony, pedicels 

 1/8' long, slender. 



Flowers: Fertile, — stamens recurved ; disc distinct, lobed; ovary globose ; style short, thick; 

 stigma broad; staminate, — stamens ascending, slender, pollen grains small. 



Berries: Very small, round or ovate, with little bloom; vinous flavor, very sweet, good 

 quality. 



Seeds: 1 to 3, usually 2; 1/6' to 1/5' long by 1/6' to 1/8' broad; oval or broadly obcordate, 

 very variable; color pale pinkish-purple; beak very short and blunt or small and acute, well 

 defined; raphe obscure or prominent, becoming a fine distinct thread to the beak; chalaza narrow, 

 in a rather deep basin, its face elevated often, or depressed, so as to appear nearly obsolete, often 

 a mere rim or crescent at base, sometimes invisible, groove extends to or over top of seed ; ventral 

 depressions short, rather wide apart, shallow. 



Plantlet: Seed-leaves medium to large, ovate, acute, green. 



Viticultural Observations and Remarks 



Germination early to medium, foKation and inflorescence medium season, ripening of fruit, 

 medium to late, exfoliation late. 



Not vigorous, weak; specimens from Western Arizona weakest; from Jeff Davis County, 

 Texas, at 4000 to 6000 feet altitude, a httle stronger with larger fruit ; from Uvalde County, Texas , 

 still stronger, some of which approach nearest to V. monticola and some to the form of V. Ber- 



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