26 MISC. PUBLICATION 273, U. 8S. DEPT. OF AGRICULTURE 
seedlings, and in hot weather a weaker emulsion should be used to 
prevent injury to the roots. While this treatment has given satis- 
factory results in the experiments so far conducted, it should not be 
adopted on a large scale until it has been demonstrated that it is 
applicable on the particular type of soil at the nursery, and puddling 
of the soil should be carefully avoided. 
Treating some soils, especially light sandy loams, with arsenical 
compounds has been shown to be destructive to seedlings, and in many 
cases it has left the ground in a toxic condition for 3 or 4 years. 
ROOT WEEVILS 
In forest nurseries of the Pacific Northwest the strawberry root 
weevil has proved to be one of the most serious insect pests. Three 
species are involved in this damage—Brachyrhinus ovatus L., B. 
rugosostriatus Goeze, and B. sulcatus F. 
The adults are small, brown, hard-shelled, wingless beetles about 
one-fourth inch in length, with head extended into a snout. When 
the adult weevils emerge in the early summer they migrate on foot, 
crawling everywhere, in search of suitable places for egg laying. 
Eggs are laid only at the root crown of plants, and the small, white, 
curled grubs develop in the soil, where they feed on the roots of 
various plants. ‘The life cycle is completed in 1 year, and the full- 
grown larvae pupate in the soil and emerge as new adults the follow- 
ing summer. 
Seedbeds can be protected from infestation by encircling them dur- 
ing the migration and egg-laying period with barriers, such as boards 
or metal strips placed on edge in the ground and painted with sticky 
substances, such as coal tar or sticky tree-banding material. Poi- 
soned baits have also proved effective in destroying the weevils in 
larger fields. An effective poisoned bait consists of 5 pounds of pow- 
dered calcium arsenate and 95 pounds of ground dried-apple waste, 
applied at the rate of from 50 to 70 pounds per acre. 
The most satisfactory method of control is through clean cultiva- 
tion and rotation of seed and transplant beds, allowing infested plots 
to remain fallow and be cleanly cultivated in alternate years. 
WIREWORMS 
Under certain conditions wireworms (Elateridae) (53) may prove 
to be troublesome nursery pests. They are most frequently found in 
heavy, moist soil, where they feed on undecayed plant material and 
small roots. These long, slim, cylindrical, hard-shelled “worms” with 
feebly developed legs are the larvae of click beetles, which are most 
easily recognized by the layman by their ability to flip into the air for 
several inches when turned on their backs. 
No satisfactory method of controlling wireworms has been de- 
veloped, and soils which are abundantly infested with them should be 
avoided for nursery purposes. 
CUTWORMS 
From time to time cutworms make their appearance in forest 
nurseries and do considerable damage to the young trees by feeding 
on the roots or clipping off seedlings at the ground line. 
