1905.] PUBLIC DOCUMENT— Xo. 88. 9 



as the apple. We observed pear trees which had their trunks 

 spUt open two or three inches hy the. frost. The erevices 

 eventuall}^ closed and conmieneed to heal over in the spring, 

 although the effects of partial root killing have left many of 

 them in a bad condition. The splitting of the stem is what 

 is termed sun scald or frost crack, and the frost and sun are 

 believed to be responsible for it. One of the characteristic 

 results of partial root killing is that the trees will bear leaves 

 in the spring and appear normal for a wdiile, wdien suddenly 

 the leaves commence to turn yellow and brown, and finally 

 dry up and drop off. If only part of the root system is in- 

 jured, the effects will show only on one or more branches or 

 limbs ; but w^hen a large portion of the root sj^stem is involved, 

 the whole tree is likely to collapse. The development of the 

 leaves of many apple trees, and in some instances of peach 

 and plum trees which had })artiall3^ leaved out, was suddenly 

 arrested, and they remained in this condition all summer. 



White pines in some localities appeared to be injured ex- 

 tensively by cold, and such native species as the white ash, 

 red and sugar maples, birches and poplars showed the effects 

 of the severe winter. The red maples exhibited in many 

 cases a scarcity of foliage, especially near the top ; and more 

 dead wood than usual was observed in some of the other 

 species noted. The effects of root killing shoAV more con- 

 spicuously when the soil moisture becomes reduced, and in 

 many cases not until the season had become quite advanced 

 did some trees show the effects of winter-killing. The etl'ects 

 on exotic plants were more severe than in 1902, since, in 

 addition to the part above ground, the roots were injured. 



Japanese maples, Japanese clematis, California privet, 

 deutzia, roses, barberries, viburnums, etc., suffered to a 

 considerable extent, and many were killed outright. This 

 list could be greatly extended, and if complete would far 

 exceed that noted in our last report. Sycamore and Norway 

 maples have sutlered from the loss of new wood during the 

 past two years, as shown by the death of terminal l)ranches. 

 Grape vine roots were affected in many cases, and in some 

 instances the maturing fruit wilted and dried u[) as if affected 

 by the black rot. 



