carry's pacific post oak. 89 



GARRY'S PACIFIC POST OAK. 



(Quereus Garryana.) 



•• What if my leaves are falling like its own." — Shelley. 



THIS White Highland Post Oak bears some resemblance 

 to the Long-acorn, or Weeping White Oak (Q. lobata), 

 although, for the most part, a smaller tree, of less maj- 

 esty, and altogether more of the old orchard-like habit; there 

 are, however, a few grand types in the interior of the State — 

 Grass Valley and elsewhere, Vancouver's Island, where we 

 observed and collected it, through Oregon as high as The 

 Dalles, and south along both coast and Sierras to San Fran- 

 cisco, in size ranging from thirty to one hundred feet or more, 

 and two to eight feet in diameter. This oak has the highest 

 northern range of any; here it could hardly be considered a 

 "mountain oak," for its altitude is below four thousand feet, 

 although sometimes so designated; so far as we know its 

 belted limits only extend from coast to foothill, preferring 

 highlands, and leaving, for the most part at least, alluvial 

 bottoms in the possession of the grander and more graceful 

 lobata. It is well to bear in mind that trees, shrubs, and 

 plants in general, observe certain lines of common average 

 temperature, technically termed "isothermal lines;" these 

 belts, or lines, are here and there slightly modified by expos- 

 ures, arborescently speaking, west and northwest, especially 

 with underlying ancient morain, being most of all favorable 

 for trees; besides, altitude as we approach the great Sierra 

 Range, becomes more important, because with similar soils 

 every hundred feet of elevation gives about an inch more 

 average rainfall; the roots also go down sixty to one hundred 

 feet or so, often intercepting much underground drainage 

 from never failing spring supplies, fresh from their alps or 

 subterranean reservoirs; while at the same time there is less 

 likelihood of killing frosts, the atmosphere being drier and 

 relative radiation less. The Garryana Post Oak is probably 

 the least strictly observant of this common law, having, as 

 we have seen, an unusually wide range. Now, the -practical 

 import, use, and hence inferences from such data are, that 

 where oaks and other forests flourish on even apparently 

 poor and esteemed inferior soils, of neglected — too often dis- 

 carded — foothills and highlands, all civilized experience, in 

 Europe, America, and elsewhere, has invariably shown them 

 to be surprisingly fertile and very lasting lands — lands most 

 eminently suitable for orchards, vineyards, olive vards, gar- 

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