1350 



PINUS 



PINUS 



c. Number of Ivs. 5: resin- 

 ducts parenchymatous . 



Pseudostrobi 16. 



CO. Number of Ivs. 3, occasion- 

 ally 4-5: resin-ducts usu- 

 ally parenchymatous. 

 Tcedce. 



D. Branchlets glaucous: 

 color of Ivs. bluish or 

 grayish green. 

 E. Lvs. slender, drooping .17. 

 EE. Lvs. stout, 6-12 in. long: 

 seeds long -winged.... 18. 

 19. 



DD. Branchlets not glaucous: 

 color of Ivs. dark yel~ 

 lowish or bright green. 

 E. Length of Ivs. 5-12 in.: 



Ivs. stout 20. 



21. 

 22. 

 EE. .Length of Ivs. 8-18 in.: 



Ivs. slender, drooping.23. 

 24. 

 25. 



BEE. Length of Ivs. 3-7 in.: 

 Ivs. stout. (See also 

 No. 20 var. ) 



p. Cones very oblique, 

 SYz-6in. long: length 

 of Ivs. usually 4-6 



in 26. 



27. 



pp. Cones not oblique, 2-4 

 in. long : length of 

 Ivs. iisually 3-4 in. .28. 

 ccc. Number of Ivs. 2. 



D. Resin-ducts parenchyma- 

 tons : cones mostly be- 

 tween the whorls. 



Lariciones 29. 



E. Branchlets glaucous . .30. 

 EE. Branch lets not glau- 

 cous. 



p. Lvs. 1-3Y?. in. long, 

 o. Cones not prickly.. 31. 



GG. Cones prickly 32. 



33. 

 34. 



pp. Lvs. $%-7 in. long. 

 G. Winter-buds brown.35. 

 36. 

 37. 



GG. Winter-buds gray- 

 ish white or silvery 

 white, oblong, not 

 resinous, only tips 

 of scales often 



light brown 38. 



DD. Resin-ducts peripheral : 

 cones usually appearing 

 at the whorls. Sylves- 

 tres. 



E. Length of Ivs. 2^-8 in. 

 p. Seeds short-winged, 



% in. long 39, 



pp. Seeds long -winged. 

 G. Branchlets not 



glaucous 40. 



41. 

 42. 



GG. Branchlets glau- 

 cous 43. 



EE. Length of Ivs. %-%% in. 44. 

 45. 

 I. STROBUS. 



Torreyana 



Sabiniana 



Coulteri */ 

 Jeffreyi 



ponderosa 



Tseda 



Cubeiisis 



palustris 



Canariensis 



longifolia 



tuberculata 

 radiata 



rigida 



echinata 

 Virginiana 



divaricata 

 clausa 

 contorta 

 pungens 



muricata 



Laricio 



Pinaster 



Thunbergi 



Pinea 



densiflora 

 sylvestris 

 montana 



green, 6-8 in. long: cones cylindric on 1-2 in. long 

 stalks, 6-10 in. long: seed brown, 4 lines long. Himal. 

 Gn. 31, p. 195. A.G. 19:149. Handsome tree, of some- 

 what loose habit, with graceful pendulous foliage, hardy 

 as far north as Mass, in sheltered po- 

 sitions. Var. zebrina, Bailly, has the 

 Ivs. with a whitish zone near the tip. 



2. Peuce, Griseb. (P. excttsa, var. 

 Peuce, Griseb.). Attains 50 ft., 

 with ascending short branches form- 

 ing a narrow dense pyramid: branch- 

 lets greenish, glabrous, not glaucous : 

 winter-buds ovate: Ivs. straight, blu- 

 ish green, 3-4 in. long: cones short- 

 stalked, cylindric, 3%-6 in. long, 

 with obovate scales: seed 4 lines 

 long. S. E. Eu. An ornamental 

 hardy Pine of dense, regular habit 

 and slow growth; forms a narrower 

 and denser pyramid than No. 3. 



3. Strdbus, Linn. WHITE PINE. 

 Figs. 1815, 1819, 1820. Attains 100, 

 occasionally 150 ft., with horizontal 

 branches in regular whorls forming 

 a symmetrical open pyramid. In old 

 age the head is usually broad and 

 open and often very picturesque. 

 Branchlets greenish or light green- 

 ish brown, glabrous or slightly pu- 1819i Pinus Stro bus. 

 berulous : winter-buds ovate, acum- (v V 1 

 inate: Ivs. soft, bluish green, 2-4 in. 



long (or 3%-5) : cones on stalks %-l in. long, cylindric, 

 slender, often curved, 2-4 in. long, with oblong-obovate 

 scales : seed red-brown, mottled with black, 3 lines long. 

 Newfoundland to Manitoba, north to Ga., 111. and Iowa. 

 8.8.11:538,539. A.G. 12:645; 13:1. Gn. 30, p. 404. -Very 

 valuable ornamental hardy Pine of rapid growth, sym- 

 metrical when young, picturesque in old age : no tree is 

 better adapted to break up the monotonous sky-line of 

 plantations in northern parks. There are a number of 

 garden forms occasionally cultivated. Var. alba, Loud, 

 (var. nivea, Carr. ). Low form of irregular habit, with 

 almost silvery white foliage. Var. brevifdlia, Loud, 

 (var. ndna, Knight. Var. pygmoza, Hort.). Dwarf, 

 compact, round bush, with short Ivs. Var. fastigiata, 

 Beissn. (var. pyramidalis, Hort.). With ascending 

 branches, of narrow pyramidal or columnar habit. Var. 

 prostrata, Arb. Kew. Dwarf, procumbent form, diffuse 

 and trailing on the ground. Var. umbraculifera, Knight. 

 Dwarf , flat-topped bush, with short Ivs. R.H. 1869, p. 

 38. There are also forms with variegated and with yel- 

 low foliage. 



4. monticola, Don. MOUNTAIN WHITE PINE. Tree, to 

 100 or occasionally 150 ft., with slender, spreading, 

 somewhat pendulous branches forming a narrow open 



1. Eustrobi. 



1. exc61sa, Wall. (P. NepaUnsis, Chambr.). Attains 

 150 ft., with spreading and slightly ascending branches 

 forming a broad open pyramid : branchlets greenish, 

 glabrous, glaucous: winter -buds cylindric - obovate, 

 acute: Ivs. slender, flaccid, drooping, grayish or bluish 



1820. Pinus Strobus (X 



pyramid: branchlets puberulous, yellowish or reddish 

 brown : winter -buds ovate, acute : Ivs. stiff, bluish 

 green and glaucous, 1/^-4 in. long, with few inconspic- 

 uous or no lines on the back: cones short -peduncled, 

 cylindric, slender, slightly curved, 5-11 in. long, yellow- 



