August, ’20] 
HERBERT: WESTERN TWIG PRUNERS 
361 
slender brown beetle about one-half an inch long, occurring in Cali¬ 
fornia and Oregon. It usually bores in at the forks of two small 
branches, entering for a quarter inch or more and throwing out con¬ 
siderable frass behind it. Young trees are occasionally quite seriously 
damaged by the attack of the beetle. 
The following is a list of the plants from which the twigs are pruned 
by this species: almond, apple, apricot, avocado, birch, cherry, cur¬ 
rant, English elm, Eugenia myrtifolia, fig, grape, live oak, olive, orange, 
peach, pear, prune, and the strawberry tree ( Arbutus unedo). 
The beetle does not breed in many of these trees, however. Its 
eggs are laid in the dead wood of acacia, almond, apple, Oregon and 
silver maple, manzanita, live oak, tan bark oak and rose. The lar¬ 
vae mine in the sap- and heartwood of these trees for a year or possibly 
more and finally emerge in the early summer as beetles to perhaps prune 
a few twigs before producing their progeny. Probably only a very 
small percentage of the emerging beetles ever assume the habit of 
attacking the small branches. 
There are no practical methods of control for the beetles entering 
the twigs. Part of the injury might possibly be prevented by the 
application of repellent or poison sprays, but the trouble seldom be¬ 
comes serious enough to warrant their use. Hand picking may be 
resorted to, but the beetle has probably already abandoned the branch 
when its condition becomes noticeable, or else most of the damage has 
been done when the beetle is found. The most satisfactory control 
measures are to destroy all possible breeding places during the winter 
or early spring by burning all dead logs and stumps of the host plants. 
Polycaon stoutii Leconte, a larger, black species, is also reported to 
prune twigs in the same manner, but has not been observed to do so by 
the writer. It breeds in California laurel, coast live oak, madrone and 
manzanita, and attacks the branches of almond and Eucalyptus 
globulus. This species occurs throughout California. 
Apate punctipennis (Leconte) (family Bostrichidse), called the 
western twig-borer, burrows into the twigs of different orchard trees, 
particularly apricot, much in the same way that Polycaon confertus 
does. It is a dark brown beetle, about one-half an inch long and 
differs from the latter in having its head well under the thorax, which 
bears prominent tooth-like processes. The western twig-borer occurs 
throughout the Pacific southwest. Mesquit appears to be its native 
host plant, but it has also been bred from the wood of apricot, fig, 
grape, pear and orange. 
Phloeosinus cupressi Hopkins and P. cristatus Leconte are bark- 
beetles belonging to the family Ipidse, which also have the abnormal 
habit of pruning small twigs. These resemble each other a great deal 
