56 EXPERIMENT STATION RECORD. 



The efficiency of this new limjiicicle in conlrolliiiij: oflicr plant diseases is to 

 bo tested. 



Timber fungi, with special reference to the pines, C. G. Rates {Ann. Rpt. 

 \cbr. Ilort. »Soc., 38 {l'J07), }i}k 201-20H). — Descriptions are given of fungi caus- 

 ing damping off of the seedlings of jiines, pine blister due to Colcosixtriion 

 scnrcioiiis, liyi)ertroi)liy of pine cones, ring scale of pine due to Trninctcs pini, 

 root rots caused l)y I'oli/iiorus annoxuH and Annillariu )iirlle(t, and dry rots due 

 to /'. raporariu.s and Mcntliiis JachrymanK. 



The treatment of damping-off in coniferous seedlings, P, Spaulding ( IJ. ti. 

 Dcpt. Afjr., liiir. nant Indus, ('ire. '/. /*//. N). — Greenhouse tests have been made 

 l>y the writer for several years relative to tlie effect of various chemicals upon 

 the daniping-off diseases of tender coniferous seedlings. The worlv was ex- 

 tended to field conditions in 1907, experiments being conducted in several nur- 

 series of the New York Forest. Fish, and Game Commission and of the Vermont 

 State Forestry Commission, located, respectively, at Saranae Inn, N. Y.. and 

 Burlington, Vt. The results presented are not considered tinal, but are offered 

 to nurserymen with the hope that they may prove useful until more conclusive 

 proof of the comparative value of the chemicals tested can be secured. 



The plats used were located in seed beds 12 ft. long and 4 ft. wide, each bed 

 being divided into 3 equal parts 4 ft. square. The chemicals were used in the 

 form of fine powders or in solutions. Tlie solutions were applied to the soil 

 with an ordinary sprinkling can before the seeds were sown and again about .^ 

 days after the seedlings had come up. The pow'ders were applied to the beds 

 only after the seedlings had been up for 3 or 4 days, a simple form of duster 

 having a perforated bottom being used. Very light coatings were given, which 

 were renewed promptly after each rain. 



Powdered sulphur was used in 3 forms, namely, washed, resublimed, and 

 pi-ecipitated, with favorable results, although the first form gave slightly the 

 best result. The preparation of dry Bordeaux mixture was found to be too 

 tedious and time-consuming to l)e of use in the case of a disease like damping- 

 off and was discarded for a copper suliihate and lime mixture which is easily and 

 quickly made. Powdered sulphate of copper was mixed with fresh slaked lime 

 1 : 10. No injurious results were noted when this mixture was freely used, even 

 when the seedlings were still wet with dew. Very good I'esults were obtained 

 in checking the damping-off, and it is believed that the mixture may prove of 

 commercial value. 



Solutions of potassium sulphid and of potassium permanganate gave no defi- 

 nite results, owing to the absence of the disease in the experimental plats. Com- 

 mercial 40 per cent formalin, used at the rate of 4 oz. to 3 gal. of water, when 

 applied to the soil before seeding and not afterwards, seemed to have no effect on 

 the disease. AVhen the application was repeated after the seedlings had come 

 up the results were poor, hence it is believed that formalin is of little value with 

 the daniping-oft' diseases of coniferous seedlings unless supplemented after the 

 germination of the seed with some other efficient chemical. 



The best results were obtained with dilute sulphuric acid. The soil was 

 thoroughly drenched with a solution of 1 oz. of sulphuric acid to 1 gal. of water 

 several days before sowing the seed, and the treatment was repeated about a 

 week after the seedlings came up. When noted in December, there was a very 

 good stand of fine, healthy seedlings on the treated plat and the soil was entirely 

 free from algre and moss, while on the check plat there w^ere practically no 

 seedlings left and the soil was green with algse and moss. Of the several species 

 thus treated, the Norway spruce alone showed ill effects from the treatment. A 

 weaker solution, 1 part sulphuric acid to 500 of water, is recommended in i^refer- 

 ence to the stronger one used iu these experiments. 



