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MISC. PUBLICATION 61, U. S. DEPT. OF AGRICULTURE 



Oaks on Long Ridge and in the Apiary plantation, chestnuts on Long 

 Ridge, and black walnut in the Black Walnut plantation illustrate 

 this. Sometimes the seed was destroyed or the plants died when very 

 young. In other instances, the trees have kept growing as a suppressed 

 understory. In the latter case, it is to be expected that a good many 

 of the hardwoods will finally take the place of the pines that drop out 

 for one reason or another. 



Another thing that Schenck had not reckoned on in planting hard- 

 woods was the large number of rodents present on or about the plant- 

 ing sites. Rodents are notorious seed destroyers in planting areas, 

 and their conduct at Biltmore was no exception. No conifer seed was 

 sown here, so all such losses were among the hardwoods. The losses 

 of black walnut and chestnut seeds, two species which were very 

 unsuccessful, have been mentioned by Schenck as particularly severe. 



After the seed had sprouted, many of the plants were killed by 

 ground mice. Schenck records that whole rows of hickory and oak 

 were destroyed by these animals working underground ; and that they 

 destroyed half of all the locust plants. 



But of all the rodents, the rabbits were the most troublesome. 

 Hardwoods that started to grow well were kept back solely because of 

 nibbling by rabbits. Rabbits were very destructive to oaks in the 

 Apiary plantation; elsewhere, sugar maples were attacked. Sugar 

 maple and oak in these plantations have been much less successful 

 than pines. On the other hand, yellow poplar has also been unsuccess- 

 ful, but it is not recorded that rabbits injured the trees. Apparently 

 none of the conifers were attacked by either mice or rabbits. 



While rodents have worked against the hardwoods, the greatest 

 damage to the pines was from insects. The southern pine beetle 

 (Dendroctonus frontalis Zimm.) has worked in shortleaf pine of two 

 plantations — Long Ridge and Ferry Farm — and another bark beetle, 

 {Ij>s sp.), has appeared in Scotch and shortleaf pines. In the Ferry 

 Farm plantation the attack included part of one of the Forest Service 

 sample plots and forced a change in the marking for thinning some 

 years after the establishment of the plot. In this stand the white 

 pines were much inferior to the shortleaf at the time the plot was 

 established; but since white pine is less subject than shortleaf to 

 attack by southern pine beetles it may ultimately supplant the short- 

 leaf should the attack be extended throughout the stand. Hardwoods 

 growing under a stand of pine attacked by the bark beetle will be given 

 a chance for development of which they are likely to take prompt 

 advantage. 



The most common insect in the Biltmore plantations is the pine 

 bark aphid (Adelges pinicortis Fitch), which infests the smooth bark 

 of white pine. Sometimes the boles are fairly white with them. 

 They are much more plentiful in the plantations than they were 10 

 years ago, and are also very common on ornamentals in Asheville, 

 but, as far as is known, they cause no serious injury to the tree. 



The white pine weevil (Pissodes strobi Peck) has not greatly dam- 

 aged the white pine on the estate. From counts of several plots 

 taken at random in the planted white pine stands, H. J. MacAloney, 

 forest entomologist with the Northeastern Forest Experiment Sta- 

 tion, estimates the proportion of the trees injured by weevils at about 

 5 per cent. No injury to the planted black locusts from the locust 

 borer (Cyllene robiniae Forst.) or the locust leaf miner (Ohalepus 

 dorsalis Thumb.) was observed. 



