PSEUDOTSUGA 



PSIDIUM 



2847 



both drought and cold. Unlike the firs, the Douglas 

 spruce has fine fibrous roots like the Norway spruce and 

 transplants as readily. The writer has transplanted 

 many stocky young trees growing in the open to the 

 nursery and has saved 90 per cent of them. They 

 seemed to thrive as well as nursery-grown Norway 

 spruces of the same size. The yield of seed from a 

 wagon-load of cones is light, and it is somewhat diffi- 

 cult to grow seedlings. In some circumstances it will 

 be cheaper in the end to procure young trees. The 

 Douglas spruce is remarkable for its wide variation in 

 form and color. The needles may be short or long, light 

 green, dark green, or have a bluish or silvery cast. The 

 deep blue and silvery foliage is" characteristic of the 

 deep gorges of high altitudes. (C. S. Harrison.) 



taxif olia, Brit. (P. Douglasii. Carr. P. mucronata, Sudw. 

 P. Lindleyana, Carr. Abies Douglasii, Landl. Abi&ia 

 Douglasii, Kent). DOUGLAS SPRUCE. RED FIB. Fig. 

 3246. Pyramidal tree, attaining 200 ft. and sometimes 

 more, with a trunk becoming 12 ft. diam. clothed with 

 ridged dark red-brown bark: branches horizontal, with 



3246. Pseudotsuga taxifolia. 



pendulous branchlets: Ivs. linear, straight or curved, 

 obtuse, slender and flexible, dark green or bluish green, 

 %-\% in. long: staminate catkins orange, pistillate 

 reddish: cones pendulous, oval-ovate, with broad 

 rounded scales and much exserted bracts 2-4J^ in. 

 long; seed J^in. long, with broad wing, light reddish 

 brown. Brit. Col. to Mex.. west to Mont, and Colo. 

 S.S. 12:607. G.F. 10:295. Gn. 31, p. 288. R.H. 1868: 

 151. M.D. 1901:1; 1909, p. 69. G.W. 10, p. 565; 13, 

 p. 411. There are many forms in cult. Var. viridis, 

 Schneid. (P. Douglasii viridis, Schwerin), is the typical 

 green-lvd. rapid-growing form. Var. casia, Schneid. 

 (P. Douglasii cassia, Schwerin), agrees with the type 

 except that the Ivs. are bluish green; it seems to be 

 somewhat hardier. Var. glauca, Schneid. (P. Douglasii 

 glauca. Mayr. P. glauca, Mayr). Of more compact 

 habit: branches more ascending: Ivs. shorter, bluish 

 green: cones smaller, with often reflexed bracts. Colo. 

 G.C. III. 36:53. Hardier than the type, but of slower 

 growth. Var. argentea, Schneid. (P. Douglasii argen- 

 tca, Koster). Similar to the preceding, with almost 

 silvery white foliage. P. Douglasii glauca elfgans, 



Mottet, is scarcely different. R.H. 1914, p. 344. Var. 

 glaucescens, Schneid. (P. glaucescens, Bailly). 

 With bluish white foliage and pendent branchlets. N. 

 Mex. R.H. 1895:88; 1903, p. 208. Var. pendula, 

 Schneid. (P. Douglasii pendula, Engehn.). With 

 pendulous branches and dark green foliage. Var. 

 glauca pendula, Schneid. (P. Douglasii glauca pendula, 

 Beissn.). With pendulous branches and bluish green or 

 bluish white foliage. Var. fastigiata, Schneid. (P. 

 Douglasii fas tigiata, Carr.). A narrow conical pyramid 

 with ascending branches and shorter Ivs. Var. com- 

 pacta, Schneid. A compact conical form with short 

 and dense foliage. Var. globosa, Rehd. (P. Doug- 

 lasii globosa, Beissn.). A dwarf globose form. M.D. 

 1905, p. 75. Var. Fretsii (P. Douglasii Fretsii, 

 Beissn.). Compact: Ivs. very much shortened. Var. 

 Moerheimii (P. Douglasii Moerheimii, Ruijs). With 

 compact habit and finer deeper blue foliage than in the 

 type. There are also some forms with variegated Ivs. 



P. japonica, Beissn. (Tsuga japonica, Shirasawa). Tree, to 60 

 ft.: branches glabrous: Ivs. shorter, emarginate, often curved: cones 

 smaller, 1 J^-2 in. long, with reflexed bracts. Japan. G.C. III. 

 45:307. S.I.F. 1:7. Has proved tenderer than P. taxifolia at the 

 Arnold Arboretum. P. macrocdrpa, Mayr (P. Douglasii var. 

 macrocarpa, Engelm. Abies macrocarpa, Vasey). Tree, to 60 or 

 80 ft., with remote and usually pendulous branches: Ivs. acute, 

 bluish gray: cones 4-6 H in. long, with shorter bracts; seeds Jiin. 

 long. S. Calif. S.S. 12:608. G.F. 10:25. Seems not yet intro. ; not 

 hardy X. P. sinensit, Dode. Tall tree: branches pubescent: rvs. 

 emarginate: cones about 2 in. long. S. W. China. Probably tender. 

 P. Darididna, Bertrand, P. Fortunei, Carr., and P. jetoensis, 

 Bertrand=Keteleeria. ALFRED REHDER. 



PSIDIUM (Greek, psidion, the pomegranate). Myrta- 

 cex. A large group of tropical and subtropical trees and 

 shrubs, all native to America, many of which produce 

 edible fruits. The common guava of the tropics, P. 

 Guajaca, is the best known. It has become naturalized 

 in many parts of Asia and Africa. See Guava. 



Leaves opposite, petiplate, glabrous, pubescent or 

 tomentose, pinnately veined: fls. usually rather large, 

 whitish, on axillary or lateral 1-3- (rarely many-) fld. 

 peduncles; calyx-tube urceolate or pyriform, lobes 4-5, 

 persistent; calyx sometimes closed before anthesis and 

 splitting irregularl}' into 2-5 lobes ; petals 4 or 5, spread- 

 ing; stamens numerous, disposed in many series and 

 inserted upon the disk, filaments filiform, anthers 

 oblong or linear, basifixed, longitudinally dehiscent; 

 ovary with 2-7, commonly 4, locules, the style slender, 

 stigma peltate or subcapitate: fr. a berry, ovoid, 

 globose or pyriform, commonly 1-3 in. long, yellow to 

 red in color, sometimes green, crowned with the calyx- 

 limb; seeds few to numerous, small, hard. About 150 

 species. The genus is somewhat confused and in need 

 of further study. A large number of species doubt- 

 less exist in S. and Cent. Amer., which have not as 

 yet been described. The genus is allied to the myrtles 

 (Myrtus), the pomegranate (Punica), and the various 

 Eugenias, of which a number are cult, in the tropics for 

 their frs. The following treatment includes the prin- 

 cipal ones known to horticulture. 



A. Branchlets ^-anyied. 



Guajava, Linn. GUAVA. Fig. 3247. An arborescent 

 shrub or small tree, up to 25 or 30 ft. high, the trunk 

 rather slender, usually dividing close to the ground, the 

 bark scaly, smooth, greenish brown: Ivs. oblong-elliptic, 

 elliptic, or oval, 3-6 in. long, lJ-2> in. broad, char- 

 taceous, rounded to acute at apex, rounded at base, 

 light green, finely pubescent below, the venation con- 

 spicuously impressed above and raised below; petiole 

 1M~2 H in- long: fls. produced on branchlets of recent 

 growth, solitary or on 2- or 3-fld. peduncles, axillary; 

 pedicel %in. long, bearing at its upper end 2 small, 

 slender bracts; calyx-tube oblong-ovate, slightly con- 

 stricted above the ovary; calyx closed before anthesis, 

 splitting into 2-4 irregular segms., whitish and sparsely 

 hairy within; petals broadly oval, about ^in. long, 

 thin and delicate, white; stamens erect or spreading, 



