Amine salts of 2,4,5-trichlorophenoxy-propionic acid (silvex) and 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) were applied to tall larkspur, Delphinium barbeyi Huth, at 2, 4, and 8 lb/A on three dates. Leaf and stem samples collected 1, 2, and 3 weeks after treatment yielded significantly higher concentrations of alkaloids than did controls. Leaves and stems from plants treated with silvex contained more alkaloids than did those treated with 2,4,5-T. Alkaloid concentration in the leaves varied directly with the rate of herbicide following the first treatment in mid-July, but this relation was not apparent in samples obtained from the third treatment in August.

This plot sprayer was designed to possess the advantages of versatility and of being self-propelled and so not competing for a tractor during the busy planting season.

The sprayer illustrated in Figure 1 is mounted on four adjustable-width, rubber-tired wheels and is self-propelled by a 2 1/2 horse-power air-cooled engine which also operates an air compressor for agitating and distributing spray materials through nozzles on the booms. The assembly of five booms can be operated singly or together and can be adjusted for broadcast or band treatment of any row width or any combination of rows up to 200 inches wide.

The sprayer was built primarily for applying pre-emergence herbicides, but the boom assemblies can be adjusted anywhere from six to twenty-four or more inches above the ground, hence postemergence spray treatments are possible. The booms are attached to a conduit support and consist of nozzles connected at 20-inch intervals by 3-inch rubber hose. Two booms extend full length along the front and back of the support with nozzles offset to provide one every ten inches. The other three booms are short. All nozzle spacings may be adjusted to varying row widths.

During 1962, barnyardgrass (Echinochloa crusgalli (L.) Beauv.) seedlings were infested by the larvae of Hyperodes humilis Gyll. The larvae attacked the growing points and the youngest tissues in the crown as well as meristematic tissues of intercalary growth. These infestations produced considerable decreases of barnyardgrass growth and yields, suggesting the possibility of effective biological control of barnyardgrass.

Weeds in row crops of the Lower Coastal Plain in Alabama were sampled by line transects in both April and August. More than 100,000 feet of transects were assayed, with detailed questioning of producers in the area. The most important weeds of summer and fall and of winter and spring are listed, with per cent coverage and per cent frequency for weeds of row crops.