68 
1c. Notwithstanding the utmost care against the invasions of 
noxious insects, occasional rotation of crops will probably be neces- 
sary, in which case the ground should ordinarily be plowed in mid- 
summer, after the picking of the fruit. 
1d. In establishing a new plantation, it is best that the new 
plants should be removed from the old field as early in spring as 
possible, as a safeguard against the deposit of eggs upon them by 
noxious insects which may be hibernating in the field and awaiting 
the opening spring for oviposition. Occasionally it becomes neces-— 
sary to take additional precautions against the, transfer of the eggs 
of injurious species from old fields to new. For this purpose the 
young plants should be set in the new field and allowed to remain 
until the runners have started and iaken root, after which the 
plants first set should be dug up and destroyed. In this way the 
field is finally stocked with plants which have not been previously 
in contact with those seriously infested. 
le. As a security against the transfer of eggs of insects laid 
upon or about the roots of strawberry plants, it is sometimes advis- 
able to wash these thoroughly after removal from the earth. 
92. BarriERS TO PROGRESS. 
2a. To prevent the entrance of hordes of injurious insects like 
the army worm, the practice of plowing a furrow around the field 
(afterwards deepened, if necessary, with a spade) has been found 
efficient, The insects accumulating in the furrow may be destroyed 
by dragging a log of wood along it, or by digging holes at intervals 
in the bottom of the furrow, in which the insects will accumulate, 
where they may be easily crushed en masse. 
2b. To prevent the spread of insects which are destitute of 
wings, and have but feeble locomotive power (like the crown-borer), 
it 13 recommended that newly established fields be separated from 
old by an interval of a few rods in width devoted to some other 
crop. 
2c. As a still greater security against such invasion from with- 
out, the practice of establishing new fields at a considerable distance 
from the old has been found especially useful. 
38. CaprurE AND Direct Destruction. 
3a. For some insects infesting the strawberry field, no cheaper 
or more satisfactory method can be used than that of capture and 
destruction by hand. 
5 b. Sweeping back and forth along the row with an ordinary 
insect net is a ready means of capture available for such exposed 
insects as do not cling closely to the plants. It may be used to 
advantage for those attacking the flower and fruit at a time when 
less laborious measures are not allowable. 
3c. For species of feeble locomotive’ power, which infest the 
leaves in summer, after the fruit has been gathered, it is a common 
and very useful practice to mow the field in dry weather, burning it 
over in a brisk wind after it is thoroughly dry. 
