ANNUAL REPORT, 1941 23 



3. Fungus attack on trees does not end when the tree becomes lifeless wood, 

 although proper seasoning and protective treatment will greatly prolong the 

 life of wood in service. Because of the neglect to consider damage from wood 

 decay fungi and related factors, extensive damage to wooden structures has 

 already been observed and additional trouble may be expected. 



For the most part, it is common knowledge that tree disease investigations are 

 essential for defense, but the importance of constant vigilance against tree dis- 

 eas s has been stressed^ in connection with work on tree problems during 1941. 

 Insidious inroads on public wealth by disease fungi would be rampant if the 

 prosecution of essential disease investigations were relaxed in favor of what, 

 for a thoughtless moment, might appear a greater defense priority need. Disease 

 investigation is primary, vital defense, and in retrospect it is basic to the strong 

 position which this nation holds today. 



Damping-off and Growth of Seedlings and Cuttings of Woody Plants as Affected 

 by Soil Treatments and Modification of Environment. (W. L. Doran.) An Ex- 

 I)eriment Station bulletin on some of the more imniediatel)-' useful results of work 

 done under this project has been published^ and is now in considerable demand. 



Work on the vej;etative propagation of white pine is being continued. Cut- 

 tings rooted in larger percentages and responded more to treatments with root- 

 inducing substances, if they were made with the basal cut at the base of the 

 current year's wood rather than at the base of wood two years old. They rooted 

 better in sand-peat or sand than in sandy soil, and, in one experiment, treated 

 cuttings rooted better in sand than in sand-peat. Best results with January 

 cuttings, 67 percent rooting, were obtained from treatment with indolebutyric \ 

 acid (200 mg./l., 5 hr.), but there was 58 percent rooting of cuttings treated with 

 naphthaleneacetic acid (100 mg./l., 4hr.), and only 13 percent rooting of the 

 untreated cuttirgs. Results were less good if cuttings w^ere taken in summer, 

 fall, or earlier in the winter. 



Much attention was given to the rooting of cuttings of hemlock and a paper 

 was published^ on that subject. Cuttings of hemlock, taken in November, rooted 

 best, 100 percent in fourteen weeks, after treatment with indolebutyric acid 

 (100 mg./l., 24 hr.), but naphthaleneacetic acid was also very effective and there 

 were indications that it is sometimes even more effective than indolebutyric 

 acid. Results obtained justify the suggestion that propagators working with 

 late-fall cuttings made of wood of the current year make some use of naphtha- 

 leneacetic acid although, with cuttings made with the basal cut at the base of 

 wood two years old, indolebutyric acid in relatively high concentrations was 

 very effective. 



A note was published^ on the rooting of cuttings of umbrella-pine, another 

 species which is usually considered difficult to propagate in this way. They failed 

 to root or to root at all well, treated or not, if taken in September or October; 

 but if taken in January, they rooted 92 percent after treatment with naphtha- 

 leneacetic acid (100 mg./l., 2 hr.), decidedly less well if treated with indolebutyric 

 acid. Rooting of December cuttings of Poncirus trijoliata was also much more 

 improved by naphthaleneacetic acid than by indolebutyric acid, and lilac cut- 

 tings responded better to naphthaleneacetic than to indolebutyric acid. But 



'McKenzie, Malcolm A. Municipal shade tree problems in national defense. Published in 

 "Proceedings of the Annual Meeting of the Mass. Tree Wardens' Assn.," February 13, 1941. 



'Doran, William L., The propagation of some trees and shrubs by cuttings. Mass. .^gr. Expt. 

 Sta. Bui. 382, 56 pp. 1941. 



-Doran, William L. Propagation of hemlock by cuttings. Amer. Nurseryman 74: 6: 18-19. 

 1941 (Contribution No. 413.) 



^Doran, William L. Propagation of umbrella-pine by hormone-treated cuttings. Florists Ex- 

 change 97:9:9. 1941. (Contribution No. 414.) 



