General Information


Diazinon 50W is a wettable powder which, when diluted with water according to the directions, is intended for the control of insect pests of agricultural crops and other plants. Do not use in greenhouses. Do not use in barns or dwellings. Do not use on livestock. Aerial application is prohibited, except as allowed on the label for use on lettuce.

In the directions for use which follow, best control is obtained when application is made when infestation is noticed. To avoid spray drift, do not apply under windy conditions. Avoid spray overlap, since crop or plant injury may result. Failure to follow the directions for use and precautions on the label may result in poor insect control, crop injury, or illegal residues.

When an adjuvant is to be used with this product, Makhteshim Agan of North America, Inc. suggests the use of a Chemical Producers and Distributors Association certified adjuvant.

Do not use water from treated cranberry beds for drinking purposes or to irrigate crops other than those appearing on EPA approved diazinon labels.

Note: The California Department of Pesticide Regulation has set a 5-day reentry period for diazinon on peaches and nectarines. Five days should elapse between the time of application and the time a worker may enter the field to engage in any activity requiring substantial contact with treated foliage. When a mixture of two or more organophosphate pesticides are applied in combination, the interval should be prolonged by adding to the largest applicable interval an additional 50% of that interval.


The required days to wait between the last application and harvest are given in ( ) after each crop name.

Limitations, Restrictions, and Exceptions


Diazinon 50W may be applied using ground application equipment as specified in the table of the label. The table indicates the minimum amount of water that can be used for application. The rate of Diazinon 50W for concentrated spray applied to fruit and nut trees by ground equipment is based on a dilute full cover spray applied with conventional ground equipment at a rate of 300 - 400 gals. of water per acre. The specific amount of product to be used appears under the separate directions for use for each crop. If the rate calls for 1 lb. of Diazinon 50W in 100 gals. of water, this amounts to 3 - 4 lbs. of product per acre when applied at the usual dilute ground spray volumes of 300 - 400 gals. of water per acre. In no case should the amount of product used per acre exceed the maximum amount per acre per application that is specified in the COMMENTS section for individual crops.

Note: To protect bees, do not apply this product to trees when trees or substantial numbers of weeds in the orchard are in bloom.

Diazinon 50W may be used during dormancy on deciduous trees and vines. When mixing with spray oils, follow oil manufacturer’s use directions.


To aid in the control of fire ants, slowly apply 1 gal. of diluted mixture over and 6 inches around each mound. Apply gently to avoid disturbing ants. Use equipment capable of delivering the diluted product as a gentle rain. High pressure sprays may disturb the ants and cause migration reducing product effectiveness. For best results, apply in cool weather (65-80°F) or in early morning or late evening hours.

- Do not apply more than 1 lb. of product per acre per application.

- A maximum of two applications are allowed per year: 1) a maximum of one as an in-season foliar application regardless of target pest and 2) a maximum of one for control of fire ant.

Pre-Harvest Interval

7 days

Restricted Entry Interval

5 days

Exception: If the product is soil-injected or soil-incorporated, the Worker Protection Standard under certain circumstances allows workers to enter the treated area if there will be no contact with anything that has been treated.