. Bulletin of the Department of Agriculture. Agriculture; Agriculture. Fig. 13.—Typical broom of tbe weeping-willow type on Doug- las fir caused by Razoumofskya douglasii. Note the long, flowing branches. Sometimes these branches are 8 to 10 feet long. without any particular hypertrophj^ of the branch as a whole. This condition is more apt to occur in dense stands. Observations by the writer on Picea engelmanni^ P. mariana^ Abies grandis^ A. lasiocarpa., A. concolor^ A. Tnagnifica, Tsuga hetero])hylla^ T. Tnerten- siana, Pinus monticola, P. alhicaulis, P. flexi- lis, P. attenuata, and oth
. Bulletin of the Department of Agriculture. Agriculture; Agriculture. Fig. 13.—Typical broom of tbe weeping-willow type on Doug- las fir caused by Razoumofskya douglasii. Note the long, flowing branches. Sometimes these branches are 8 to 10 feet long. without any particular hypertrophj^ of the branch as a whole. This condition is more apt to occur in dense stands. Observations by the writer on Picea engelmanni^ P. mariana^ Abies grandis^ A. lasiocarpa., A. concolor^ A. Tnagnifica, Tsuga hetero])hylla^ T. Tnerten- siana, Pinus monticola, P. alhicaulis, P. flexi- lis, P. attenuata, and other conifers show that brooming of the branches is a common phe- nomenon attending mistletoe infection of these species. The weight of these brooms on many coni- fers is frequently sufficient under stress of winds and rain to cause the branches to split from the trunk, or to break farther out if the brooms are located far out from the trunk. This very commonly occurs in the case of Fig. 14.—Typical brooms of old infections on western larch caused by EazouDiofskya lari- cis. Very few of tbe origi- nal branches remain, and they are heavily broomed and covered with lichens. The old branches are replaced by short scrubby secondary branches. Note that two of the original branches still re- main, but are Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original United States. Dept. of Agriculture. [Washington, D. C. ?] : The Dept. : Supt. of Docs. , G. P. O.
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