Ixxxvi Department of Horticulture 



II. INVESTIGATION. 



Aside from the investigations reported by Professors Wilson and 

 Judson, a few others were conducted by the Department. 



(a) Ericaceous plants in relation to lime. — An interesting study 

 that has been in progress for the last three years bears on the 

 growth and behavior of ericaceous plants in relation to limy soils. 

 The study is being made in a co-operative way with one of the 

 large propagators of this class of plants, and arrangements have 

 just been completed for an extensive test of rhododendron and other 

 heaths under outdoor conditions, with a view of ascertaining the 

 possibility of preventing the injurious effects of lime by use of an 

 antidote. The cultivation of rhododendrons is seriously restricted 

 in certain parts of the country by reason of the excessively limy 

 conditions of the soil. 



(b) Peony. — The peony study commenced five years ago in co- 

 operation with the American Peony Society continues. A new plant- 

 ing of those varieties that are now recognized as being authentic 

 has just been completed, which will stand as the nucleus of a peony 

 garden which we hope to have established here in the near future. 

 Preparations are being made for the addition of a full list of the 

 tree peony to the herbaceous collection. The work is now in charge 

 of Mr. L. D. Batchelor. 



(c) Hollyhocks. — A co-operative study of the herbaceous mem- 

 bers of the genus Althea has been in progress with the Department 

 of Plant Pathology for the past two years. The past season the 

 plants flowered, systematic studies were made, and herbarium speci- 

 mens were added to the garden herbarium. The study includes an 

 investigation of the hollyhock disease on the part of the Depart- 

 ment of Plant Pathology, together with a monographic study of the 

 group by the Department of Horticulture. 



(d) Hedge plant studies. — Over fifty species of trees and shrubs 

 have been set out for the purpose of studying their adaptation for 

 hedging. These plants were furnished free of charge by Isaac 

 Hicks & Son, Westbury Station, Long Island. They will afford a 

 permanent object lesson on the value of coniferous and deciduous 

 trees and shrubs to all those interested in the planting of hedges. 



(e) Influence of soil and temperature on plant grozvth. — This 

 year has closed the fourth season s work on this subject. The in- 

 vestigation has been conducted by Mr. H. B. Frost under the direc- 

 tion of this Department. A large amount of valuable data has been 

 collected, which will be presented for publication as early as pos- 

 sible. 



