EXPERIMENTS WITH TREE SEEDS. 135 
DRILLING versus BROADCASTING SMALL TREE SEEDS. 
A series of beds were stocked with the seed of the spruce, 
which, in certain cases, was sowed in rows, and, in other cases, 
broadcast. The testing of these two systems of seed-distribution 
was expected to prove interesting, the one (drilling) being 
almost universally practised on the Continent, while the other 
(broadcasting) is the common system in this country. 
The figures which our experiment furnished cannot be regarded 
as reliable, the disturbing cause in this case being surface cater- 
pillars, which are the larvz of various species of Noctuide, such as 
the Heart and Dart and Great Yellow Underwing Moths. In 
the autumn succeeding the spring in which the seed had been 
sowed, we began to notice that the stems of many of the young 
spruces were bitten through, the upper part of the plant being 
found lying on the ground or suspended by a thread of bark. 
At first we suspected that the damage was due to mice; but on 
turning up the soil to the depth of a couple of inches, we found 
that the depredators were brown or slaty coloured fleshy cater- 
pillars, about 14 to 2 inches in length, and furnished with eight 
pairs of feet. These so-called surface caterpillars are almost 
omnivorous in their tastes—so far as a vegetable diet is con- 
cerned—and are well known to gardeners as attacking turnips, 
lettuce, cabbages, cress, and a variety of other plants. During 
the day they lie coiled up and concealed in the soil or underneath 
clods, stones, etc., while at night they crawl to the surface and 
feed upon the stems and lower foliage of plants. Although they 
ruined our experiment, they were the means of demonstrating one 
advantage of having seedlings in rows, for, where the young trees 
were growing in this way, it was a simple matter to turn over 
the soil between the rows and destroy the pests, whereas nothing 
could be done where the seed had been broadcast. Sixty-six 
caterpillars were thus collected on the 33 square yards of drilled 
seed-bed, the removal of these pests being doubtless the reason 
why the drilled beds produced 1150 plants, as against 516 on 
the beds that had been broadcast. 
How sHoutp Acorns BE LAID IN THE GROUND. 
This experiment, and those that follow, were started in the 
autumn of 1893, and the results were determined in the spring 
of 1897, when the plants were three years old. 
