WINTER PROTECTION OF THE PEACH. 



"Xn. YTUMEROUS experiments in 

 I \\ I protecting the peach against 

 j\ Vl winter killing have been car- 

 ried on at the Missouri Ex- 

 periment Station during the past two 

 years. The results of these trials are 

 reported by Prof. J. C. Whitten in bul- 

 letin thirty-eight of that station. The 

 bulletin is illustrated with cuts showing 

 different methods employed, and is for 

 free distribution among the peach grow- 

 ers of the Mississippi Valley. In this 

 latitude, winter killing of the fruit buds 

 of the peach is usually due to the un- 

 favorable effects of freezing, after they 

 have been stimulated into growth by 

 warm weather during winter or early 

 spring. It is seldom that the tempera- 

 ture drops sufficiently low to injure dor- 

 mant peach buds. Peach fruit buds may 

 safely endure a temperature of lo or 20 

 degrees below zero, provided they ma- 

 ture well in autumn, are entirely dor- 

 mant, and the cold comes on gradually. 

 Zero weather may kill fruit buds that 

 have swollen during previous warm days, 

 or that were not properly ripened in 

 autumn. The early swelling and growth 

 of the buds is due to the warmth they 

 receive from the sun on bright days, is 

 practically independent of root action, 

 and may take place on warm, sunny days 

 in winter, while the roots are frozen and 

 dormant. Shading or whitening peach 

 trees to prevent their absorbing heat on 

 sunny days, opposes growth of the buds, 

 and is, consequently, a protective mea- 

 sure. Whitening the twigs and buds by 

 spraying them with lime whitewash is, 

 on account of its cheapness and beneH- 

 cial effects, the most promising method 

 of winter protection tried at the station. 

 These whitened buds remained practi- 

 cally dormant until April, while unpro- 

 tected buds swelled perceptibly during 



warm days late in February and early in 

 March. Eighty per cent, of the whit- 

 ened buds passed through the winter 

 safely, while only 20 per cent, of the 

 unwhitened buds escaped winter-killing. 

 Whitened buds blossomed three to six 

 days later than unwhitened buds. Ther- 

 mometers covered with material the 

 color of the peach twigs, registered, dur- 

 ing bright sunny weather, from 10 to 

 over 20 degrees higher than thermome- 

 ters covered with white material of sim- 

 ilar texture, thus indicating that whit- 

 ened peach twigs might be expected to 

 absorb much less heat than those that 

 were not whitened. The whitewash 

 used was four parts of water, one part of 

 skimmed milk, and enough freshly 

 slaked lime to make as thick a wash as 

 could conveniently be pumped through 

 a Bordeaux spray nozzle without clog- 

 ging. This wash was sprayed on the 

 trees by means of a bucket spray-pump. 

 The first application was made the last 

 of December, and three subsequent 

 sprayings were necessary to keep the 

 trees thoroughly coated until spring. 

 The cost for material and labor is about 

 40 cents per tree, when done on a small 

 scale. 



Shading the trees with canvas hay 

 covers was about as beneficial as whit- 

 ening, but was more expensive. " Bal- 

 ing," by drawing the branches toeether 

 is a vertical bundle and covering them 

 with coarse grass and corn-stalks, pro- 

 tects the buds. Old trees with stiff 

 branches cannot well be treated in this 

 manner without injury to the branches. 

 " layering," or bending down the trees 

 in autumn, and covering them with 

 earth, has proven beneficial. Shading 

 the trees with broad sheds enabled peach 

 buds to survive the winter uninjured, 

 when 80 per cent, of unprotected buds 



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