108 ELEMENTARY FORESTRY. 



cans laid on their sides, so they may be readily found in spring 

 and will not be liable to poison the birds. When seedlings are 

 thrown out of the ground by frost they should be pushed back 

 and have the earth pressed against them as soon as the ground 

 is thawed in the spring. 



I/ate Spring Frosts are common in the low lands of this 

 section. They injure the trees by killing the new spring growth 

 after it has started several inches. A large number of trees are 

 seriously injured in this way, and are classed as frost tender 

 trees, and those that are not liable to this injury are termed 

 frost hardy trees. Among conifers the spruces and balsams 

 are much injured by late spring frosts, while our pines and the 

 Tamarack, Red Cedar and Arborvitrc are seldom if ever injured 

 in this way. Deciduous trees recover from such injuries more 

 quickly than evergreens. Among the deciduous trees mast lia- 

 ble to injury from this cause are the Ash, Mulberry, Oak, Maple, 

 Basswood, Black Walnut, Butternut and Boxelder, though they 

 do not all suffer in the same degree. Among those that are not 

 sensitive to late frosts are the Elm, Willow, Poplar, Birch, Hack- 

 berry, Wild Black Cherry and Mountain Ash. 



On account of this liability to injury from late frosts, : t is 

 customary to study the probability of damage from this cause in 

 given locations, and to plant accordingly. It will often be found 

 that in certain low spots there is greater liability to late frosts, 

 while there is very little injury from this cause on the higher 

 lands. It is customary among European foresters to protect 

 young seedlings of some kinds, particularly Beech, from late 

 frosts until they get up off the ground. For this purpose Birch 

 twenty or more feet high are encouraged at intervals of thirty or 

 forty feet, and the frost tender plants, such as Beech and Spruce. 

 are set out between. The result of this arrangement is that the 

 Birch, which is frost hardy, quite successfully protects the frost 

 tender trees below it. After the frost tender trees are well "ft 

 the ground, as ten or fifteen feet high, there is comparatively lit- 

 tle danger from this source of injury, and the I'.irch i> remme.l. 



Sleet Storms occasionally do much damage by breaking the 

 limbs. Little can be done to relieve the trees, but preventive 

 measures may be taken. If no large crotches are allowed to 

 form in trees, and growth kept as near as possible to one cen- 

 tral shaft, or .the longer branches shortened 90 as they will noi 



