26 BULLETIN 308, U. S. DEPARTMENT OF AGRICULTURE. 
(6b) The broods of the beetle in the bark of the main trunks of the medium 
to larger-sized dying infested trees within an area of 8 or 10 square miles or 
more must be destroyed in order to stop their depredations. 
(c) The broods may be destroyed by one or more of the following inethoae 
the work to be done between the 1st of November and the ist of March: 
(1) Removing and burning the infested bark from the trunks of the stand- 
ing trees; or 
(2) Removing and burning the infested bark from the trunks of the trees 
after they have been cut down; or 
(3) Scorching the infested bark or burning the wood with the bark after the 
trees are cut down; or 
(4) Placing the infested portions of the trunks in water; or 
(5) Converting the trunks of the infested trees into cordwood and using the 
wood for fuel before the beetles leave the bark; or 
(6) Converting the infested trees into lumber or other products and burning 
the slabs or bark. 
(d) It is not necessary to burn the tops or branches of treated trees or to cut 
and burn small infested saplings if the larger infested trees are disposed of. 
(e) It is not necessary to remove or destroy the bark on the lower portion of 
the trunk or on the stumps if it is not infested with the destructive beetle, and 
it is not necessary to cut or treat dead trees from which the beetles have 
emerged. 
(f) It is necessary and essential that the broods of the destructive beetle in 
the bark of any portion of the main trunks of the medium to larger sized dying 
infested trees of any given locality should be destroyed. 
(g) If the wood of the infested trees can be utilized for fuel, lumber, or 
other purposes, its value should cover the cost of the work. If the work of 
felling and barking the trees is done at direct expense, the cost will average 
10 to 30 cents per tree. 
(nh) The cost of protecting the living timber of.any locality with average in- 
festation should not exceed an average of from 1 to 5 cents per acre for the 
total area of pine-covered land, and if estimated on a basis of volume it should 
not cost over 2 cents per cord of the living timber protected. 
(i) The best time to conduct control operations against the southern pine 
beetle is during the period between November 1 and March 1. 
(j) If a pine tree standing among or near a grove or woods of living pine is 
either struck by lightning or felled and barked or split into cordwood during 
the summer and early fall, it will, as a rule, attract the beetles within a radius 
of 3 or 4 miles and result in the starting of a new center of infestation and in 
the death of a large number of trees. 
(k) The principal owners of pine in each community should cooperate in the 
disposal of the required infestation, but should not undertake the work until 
some one or more of the owners is sufficiently familiar with the essential details 
of the proper methods. 
The pine tip moth (Letinia frustrana Scud.) attacks and deforms 
the growing tips of branches. In some localities this is the most 
noticeable cause of injury and is sometimes very abundant for several 
successive years. There is no practical means of controlling the insect 
under forest conditions. The injury is least in suppressed parts of 
trees, or trees growing beneath older forest stands and greatest in 
thrifty stands of reproduction from 4 to 10 years old growing in old 
