DEPARTMENT OF AGRICULTURE


under fairly good conditions topping early is advantageous.
It is difficult to have all plants in a field reaching maturity
at the same time, however, a good balance between the fer-
tility practice and adequate moisture aid tremendously in
the control on the frequency that tobacco should be suckered.
 Early transplanted tobacco, followed with cool, wet weather
 tends to button prematurely. This early flowering may cause
 the tobacco to be of small leaf and of poor quality. To over-
 come this it is often advisable to top, or cut the stalks down
 to a height of 6 to 8 inches and then select a good sucker on
 the second or third leaf from the top. Top-most suckers should
 not be selected because they break-off more easily during
 windy weather.
 Topping and suckering have previously been done by hand
labor, which at present is both expensive and scarce; however,
the use of chemicals are satisfactorily replacing the need
for the time consuming hand labor and expensiveness of this
operation in tobacco culture.
 Maleic hydrazide (MH-30) is a chemical hormone that is
commonly used, an herbicide recommended for use in con-
trolling suckers on tobacco, provided careful consideration is
given to maturity of plants, and that dosage recommendations
are followed closely.
 Eighty to ninety percent of the plants should be in flower
before spraying with maleic hydrazide. Figures 19 and 20
show sucker control with and without MH-30.
 Plants that have not reached full maturity will probably
show retarded leaf development if MH-30 is applied to them.
The chemical may be applied to both topped and untopped
plants, also it may be applied over the entire plant or only a
part of it, since the material is translocated to the active
growing regions of the plant.
 Maleic hydrazide is used at the rate of from 5 to 7 pints
per acre, or approximately 1 pint per 1200 plants. (See table 7).
In any case it is the concentration and uniformity of spray
application on each plant that is important. Airplane appli-
cation of the material is not recommended.
 Sucker control is not recommended under unusually dry grow-
ing conditions if the tobacco has been heavily fertilized (1,500