42 BULLETIN No. 82. 



this layer and derive sustenance from the soil beneath. A ground fire, 

 which destroys the thick layer of undecomposed litter, is very favor- 

 able to reproduction, provided that there is plenty of pine seed dis- 

 seminated over the area after the fire, and before undergrowth and 

 weeds have a chance to completely seed up the ground. 



3. Open situations, whether in the forest or on cleared areas, are 

 most conducive to pine reproduction, as the seedling here has full en- 

 joyment of sunlight. Reproduction in the open forest takes place un- 

 der the same conditions as described for the broken forest, but the in- 

 creased amount of light makes the seedlings more vigorous. On areas 

 cleared by lumbering, germination is fair, and the seedlings grow well, 

 provided there is no dense growth of underbrush and weeds, or a thick 

 layer of undecomposed litter. Fire after lumbering is very favorable 

 for reproduction from seed falling after the fire, but kills all the seed 

 already on the ground. The reproduction from seed dissemination on 

 idle farm land of all kinds is always good, to which fact the hundreds 

 of acres of abandoned agricultural land covered with young pine at- 

 test. Unused, plowed land, with soil directly exposed, is most favor- 

 able for loblolly reproduction. 



The seedlings, once established, show a strong and rapid develop- 

 ment provided they have abundant light. The roots are well developed 

 and deep-growing in the first year, and the seedlings are hardy against 

 climatic factors from the very start. 



Enemies. The thick bark of loblolly pine makes it an exception- 

 ally good fire resister. Except where the undergrowth is very dense 

 there is little danger of loblolly thickets being destroyed by fire after 

 they are about ten years old or 20 feet in height. Loblolly on dry, 

 sandy ridges suffers much more from ground fires than on moist bot- 

 tomland. Although at the time of the fire such stands are apparently 

 not damaged, yet many trees are weakened and later succumb to at- 

 tacks of insects and fungi. There are never any very extensive forest 

 fires in Delaware because the country is so much broken up by roads, 

 streams, and cleared farm lands. It is comparatively easy for the for- 

 est owner to keep out fire entirely from the young stands which require 

 protection most. 



Dominant trees of loblolly pine, which have never been injured by 

 fire or broken by the wind, are seldom attacked by fungi or insects, due 

 to their great vitality and resisting powers. Suppressed trees, how- 

 ever, and those which have received physical injury become very sus- 

 ceptible to such attacks. Loblolly is not a long-lived species because as 



