sease progresses more rapidly in plants that have made a
succulent, luxurious growth, while those with hard, woody stems resist
it somewhat.

_The disease is due_ to the invasion of bacteria, which enter the leaves
through the aid of leaf-eating insects, or through the roots. They plug
the water-carrying vessels of the stem, shutting off the water and food
supply of the plant. If the stem of a plant freshly wilted from this
disease be severed, the bacteria will ooze out in dirty white drops on
the cut surface.

=Remedial measures= entirely satisfactory for the control of bacterial
wilt have not yet been worked out. The best methods to adopt at present
are the following:

(1) _Rotation of crops._--The field evidence is that this disease is in
many cases localized in old gardens or in definite spots in the field.
It appears also that the infection left by a diseased crop can remain in
the soil for some time. It is therefore advised that tomato growers
should always practice a rotation of crops, whether any disease has
appeared or not, and that in case bacterial wilt develops they should
not plant that land in tomatoes, potatoes, or eggplants for three or
four years. The length of rotation necessary to free the soil is not
known, but will have to be worked out by the individual grower.

(2) _Destruction of diseased plants._--The bacteria causing wilt not
only spread through the soil but are carried by insects from freshly
wilted to healthy plants. Diseased plants thus become dangerous sources
of infection, and it is evident that all such should be pulled out and
burned. This is particularly important at the beginning of the trouble
when the eradication of a few wilting plants may save the remainder.

(3) _Control of insects._--To lessen the danger from spread of wilt by
insects, the measures advised in the next chapter for the control of
leaf-eating insects should be adopted. In this connection it should be
mentioned that the use of Bordeaux mixture for leaf blights, as
previously recommended, has an additional value in that the coating on
the leaves is distasteful to insects and helps to keep them away.

(4) _Seed selection._--Work done at the Florida experiment station
indicates that resistant varieties may be secured, but there are as yet
none in commercial use. This is an important line for experimenters to
follow up. There is no proof that the disease is spread through seed
from diseased plants.

=Fusarium wil