In the August number of the Horticulturist you have given the dimensions of several trees in Western New York, with an invitation to correspondents in various parts of the Union to furnish accounts of trees of remarkable size. Take, then, two or three samples of Oregon growth of timber, not the largest that her genial climate has coaxed up into the sky, from this rich, prolific soil, but the largest around which I have yet put my tape line. It may be safe, however, for you to "stand from under" with your dwarf specimens from the Genesee Valley.

A fir tree standing on the farm of Judge Strong, at Cathlamette, twenty-five miles above Astoria, on the Columbia river, has the following dimensions: Diameter, five feet above the ground, where it is round and sizeable, 10 feet; height to the first limb, 112 feet; height of the tree, 242 feet The trunk is perfectly straight, diminishes very gradually, and the whole tree is beautiful; yet in this respect not singular, for our forests are composed of trees lofty, straight, and beautiful.

A spruce tree, standing on the bottom lands of Lewis and Clark's river, twelve miles from Astoria, measured accurately with the tape five feet above the ground, is thirty-nine feet in circumference. The place of measuring is above the swell of the roots. The trunk is round, and with a regular and slight diminution runs up straight and lofty. We did not ascertain its height. Nor is it "alone in its glory," but in a forest of spruce, cedar, and fir, some of the trees of nearly and perhaps quite equal size.

Gen. John Adair, of Astoria, informs me that about three years ago he bought a hundred thousand shingles, all made from one cedar tree, for which he gave fifteen hundred dollars in gold.

The forest trees of Oregon are remarkable for their straightness, loftiness, and very gradual diminution in size. They are destitute of large branches, and have comparatively little foliage. Two hundred feet in length of saw-logs have been cut from a tree, the smallest end being sixteen inches in diameter. Lewis and Clark "measured a fallen tree of that species, (fir,) and found that, including the stump of about six feet, it was three hundred and eighteen feet in length, though its diameter was only three feet"

One of our citizens has received an order from London to cut one of our tall trees into segments, and ship it to that city, there to be erected to adorn the crystal palace. It will be done. Those persons, therefore, who desire it, will be able to examine an Oregon forest tree, with its top pointing up among the clouds that envelop the metropolis of England.

[We hope Mr. Cos will find more such interesting items to communicate. - Ed].