. Bulletin of the Department of Agriculture. Agriculture; Agriculture. MISTLETOE INJUEY TO CONIFERS, 11 able trees. Considering the severity of the infection, they could not be expected to attain near the size of their parents shown in Plate III, figure 1, and from which they received the mistletoe. Of the 245 infected seedlings, 49 were dead. An examination of the root system of each seedling showed it to be well developed. In the absence of any other deteriorating influence except an occa- sional needle infested by Chionaspis pinifolia Fitch, the death of these seedlings must be ascribe
. Bulletin of the Department of Agriculture. Agriculture; Agriculture. MISTLETOE INJUEY TO CONIFERS, 11 able trees. Considering the severity of the infection, they could not be expected to attain near the size of their parents shown in Plate III, figure 1, and from which they received the mistletoe. Of the 245 infected seedlings, 49 were dead. An examination of the root system of each seedling showed it to be well developed. In the absence of any other deteriorating influence except an occa- sional needle infested by Chionaspis pinifolia Fitch, the death of these seedlings must be ascribed to the lux- uriant growth of mistletoe which they had supported (fig. 5). In most cases the tufts of mistletoe had fallen away. The bark of the large fusiform swellings was usually ruptured and both the wood and bast tis- sues were so heavily infil- trated with pitch that the passage of food materials between the crowm and the roots was wholly impossible, resulting in death. In this respect there is a parallel between this type of mistle- toe injury to seedlings and that resulting from the perennial mycelium of some caulicolus Peridermiums. A further study of the large trees shown in Plate III, figure 1, is illuminating. Two of them, the right and the left in the figure, are dead. Scarcely a single normal branch is to be seen, but instead are numerous large gnarled and distorted brooms. These trees measured on an average inches in diameter at 4^ feet from the ground, and increment borings showed the age of each to be 190 years. This is far below the diameter of normal trees of the same age for the region. A careful search for secondary causes of injury resulted negatively. The trees were absolutely sound. Lightning injury, which sometimes causes spiketop in yellow pine and other conifers and which sometimes is erroneously attributed to mistletoe, was not present. With the evidence in hand, it is safe to state that the trees. Fig. 8.—A group of Douglas firs with their en
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