II. Suggestions for weed control programs

 J. R. Orsenigo V/
 As indicated earlier, one particular weed must be eradicated to control
 potato virus Y infections; that weed is NIGHTSHADE (Solanum gracile and/or
-S. ig ). Another host plant, the ground-cherry (Physalls sp.) is not
common in the Florida East Coast area and where present is controlled by
treatments intended for nightshade.

 Wild cucumber, Melothria pendula, the host of watermelon: mosaic virus
 is also controlled by these treatments.

 Herbicide suggestions:

 Off-Season: (June, July, August); fields and ditchbanks:

 1. Flame (weed burner) particularly LP gas burners'operating at 20000
 or higher temperatures. A repeat application two to three weeks after
 the initial burn will be necessary.

 *2. 2, 4-D plus 2,4,5-T: use amine salt or low volatile ester formulations;
 each at 3/4 1b/A, acid equivalent 4/ Approximate cost of this 1 1/2 lb/A
 acid equivalent treatment: $2.50 A.

 *3. 2,4-D plus 2,4,5-T: amine salt or low volatile ester formulations;
 each at 1 Ib/A, acid equivalent. Approximate cost of this 2 lb/A acid
 equivalent treatment: $3.50/A
 *4. 2,4,5-T: amine salt of low volatile ester formulations t 1 1/2
 Ib/A acid equivalent. Approximate cost of this treatment is -,40/A.

 Application hazards: When applied properly, 2,4-D, and 2,4,5-T "hormone
type" materials should present no problems in the "off-season." See
spraying practices-below.

 3/ Assistant Horticulturist, Everglades Experiment Station, Belle Glade.
 Indicates recommended treatments

 k/ These chemicals are purchased as liquids and several concentrations
are available. Probably the most common contained 4 lb/ gallon, acid
equivalent; therefore, a 1 lb/A rate would require one quart to treat one
acre. Combinations of 2,4-D and 2,4,5-T (brush killer) herbicides are
commercially available. However, it may be considerably more economical
to buy 2, 4-D and 2,4,5-T separately and mix in the tank at time of spraying.
If purchased separately be sure to use the same formulations; preferably
from the same manufacturer or formulatcr.