MISSOURI BOTANICAL GARDEN 
DESCRIPTION 
Dark-bodied, minute, 
sucking insect, causing 
discoloration and death 
of foliage 
Large, naked, green 
worm with a curved 
. horn near the hind end 
and seven oblique lines 
along sides 
Hairy aco sal 14 in. 
long, yellow, striped 
with black, four tufts 
of white hair on back, 
black hair at hind end; 
head bright red with 
a pencil of black hair 
projecting on either 
side : 
Dark-colored snout 
beetle infecting stored 
products 
Se eee ee 66.4 CS 
se eee 
tee eee 
602 858 Soe eS 
ed 
side of leaves 
BULLETIN 25 
CoNnTROL 
Spraying or fumigation 
with tobacco 
Arsenate of lead 
Arsenate of lead 
Carbon bisulphide fumi- 
gation 
Hydrocyanic gas fumi 
gation 
THE INGROWN ROCK 
A trip through the rocky hillsides of Missouri reveals 
many interesting features of the adaptation of plants in gen- 
eral and trees in particular to the environment and m 
peculiar specimen of an 
with a large limestone 
one-half ton imbedded in tissues of 
during the early stages of the growth 
the trunk was wedged tightly 
of growth. Plate 6, fig. 1, shows a 
old bur oak (Quercus macrocarpa), 
rock weighing fully 
the tree. Apparently 
of this tree, 
edia 
against a ledge. 
The continued pressure of trunk growth against the rock 
caused a wound, arresting sap activity at this 
point and 
forcing the cambium tissue to envelop the rock in its efforts 
to find 
roper room for expansion. 
died, and 
The tree has finally 
a portion of it with the imbedded rock has been 
transferred bodily to a position similar to its natural sur- 
roundings in the reconstructed Linnean House. 
A feature of more common 
throughout the various ledge formations, is : 
cleavage and elevation 
A root reaching a fissure in the rock is able 
force exerted by the roots of trees in 
of huge rocks. 
occurrence, 
noticeable 
the mechanical 
to crack the stone and shatter it by its further thickening. 
It has been estimated that a wei 
by growth of a root only ten inches in 
to Kerner and Oliver, this 
t of two tons may be lifted 
diameter. According 
burden is small in comparison 
