22 BULLETIN 46, HAWAII EXPERIMENT STATION. 
ing, but one that also requires no irrigation and very little tillage. 
Such a crop would mean only little extra time and expense over the 
time-honored custom of leaving the fields fallow. 
No doubt it would be practicable for many of the sugar and pine- 
apple plantation owners to seed their otherwise fallow lands to 
pigeon peas. This practice would not only result in preparing the 
soil for the subsequent crop of sugar cane or pineapples, but it would 
enable the plantation owners to maintain considerable herds of dairy 
cows and other live stock; these in time would do much to increase 
the local food products and the importance of this can not be over- 
estimated in a scheme of permanent and economical agriculture. 
PESTS AND DISEASES. 
Thus far the pigeon pea has been comparatively free from pests, 
with the exception that, as already noted, the seeds in storage are 
subject to weevil attack, as are the cowpea and a number of other 
leguminous seeds. 
In common with all } T oung seedlings, the pigeon-pea crop may be 
considerably injured during the first few weeks of its development, 
especially in certain seasons, by the attacks of cutworms and army 
worms. However, seasonable planting has made it possible to escape 
these pests in extensive plantings at the station. Again, as it develops 
from spring plantings, the young terminal growth may, when condi- 
tions are favorable, be attacked by plant lice or aphids. However, 
like the cowpea, the pigeon pea does not seem to suffer any perma- 
nent injury from such attacks. Occasionally the Japanese beetle 
and other leaf -eating pests attack the foliage, but such injury, par- 
ticularly in extensive plantings, is negligible. 
As the plants make dense, mature growth, especially in sheltered 
areas, they may be infested with both the cottony cushion scale 
and the mealy bug. These pests, however, are kept fairly well in con- 
trol by parasites and the common ladybirds. There is some evidence 
that the myna bird also feeds upon clusters of the cottony cushion 
scale. 
During the past year harvesters experienced some annoyance 
from the common wasp. This insect builds its comb in densely 
growing shrubs, and when disturbed by harvesters in cutting the 
upper branches of the infested pigeon pea for forage, it retaliates 
with a more or less formidable sting. 
In addition to the Coccida? already mentioned, several other scale 
insects have been found to infest the pigeon pea. The most serious 
of these {Coccus elongatus) has been under observation during the 
past year as it has been the cause of much concern. In at least two 
extensive plantings on the island of Maui, large areas have become 
