Phillips — Hail Injury on Forest Trees. 55 



succulent wood. Large, succulent leaves were much worse 

 affected than linear leaves, cut leaves, or leathery leaves. 

 Coppice was more seriously affected, because of the more 

 succulent growth and also because it retains smooth bark 

 for a much longer period, than seedling growth. An es- 

 pecially noteworthy feature of the injury was noticed in 

 the growth of the new leaves where entire defoliation had 

 taken place. In every case the first leaves developed at 

 the ends of the growing shoots, when the shoots were not 

 badly wounded. If the shoots were broken or severely 

 lacerated, the first leaf developed from an adventitious 

 or a dormant bud back of the injury. Such leaves were 

 usually at least one week in advance of all other leaves. 

 Lateral leaves further down the shoots continued to 

 appear from 3 to 4 weeks after the first leaves, thus caus- 

 ing a very irregular and prolonged leaf development. The 

 retention of thick, leathery leaves such as occur on osage 

 orange aids materially in protecting the shoots. In 

 Europe 5 the removal of the forest is said to increase the 

 frequency of hail. 



The injury to forest trees caused by hail is especially 

 likely to induce secondary injuries from forest fungi and 

 insects. In cases of severe injury to shade trees it would 

 be well to trim off the branches most severely affected and 

 to watch carefully for insect or fungus infestation. As a 

 result of two years' observation there seems little doubt 

 that hail injury increases the infestation of hardy catalpa 

 by dry rot (Polystictus versicolor Fr.). Hardy catalpa 

 does not recuperate readily from hail injury and most of 

 the plantations, windbreaks and shelterbelts in the state 

 show the effect of some hail storm of the past. In such 

 plantings it is a common occurrence to find wounds ten 

 to twenty years old which have not healed over and such 

 badly wounded branches often show a great deal of 

 fungus action. Some of the wounds show a secondary 

 injury by insects, but so far this is limited. Most of these 

 wounded trees are also characterized by water sprouts 



5 Houston, E. J. Outlines of Forestry. 147. 1893. 



