As spring activities begin, farmers are reminded that sprayers and tanks need to be inspected for damage or degradation.

Calibration is the first and sometimes only inspection that an applicator conducts on their sprayer. While this is necessary and recommended, it is not the only aspect of spray equipment that requires regular inspection and maintenance.

Polyethylene tanks, or poly tanks for short, are extensively used on farms in Michigan. These tanks are very versatile and readily available.

Depending on how they are used and the environmental conditions they are exposed to, poly tanks have a varied lifespan. Those used for chemicals and other caustic materials will eventually weaken and fail.

Tank integrity is measured by three indicators: scratches, crazing and cracks:

• Scratches are on the surface and can be seen and felt.

• Crazing is a network of fine lines or cracks that may look like a patchwork, but often cannot be seen with a visual inspection. Crazing can be seen when using one of the testing methods explained below. Crazing occurs within the tank wall and can be a sign of deterioration of the plastic, which may lead to cracks. Tanks that show signs of crazing will still hold liquids, but the integrity of the tank is questionable. For this reason, caution should be used when putting any hazardous substance in tanks that show crazing.

• Cracks extend through the plastic wall and can be visually seen and felt. Cracks may run parallel or at right angles to each other.

Testing poly tanks is a simple procedure. If you purchase a new tank you should fill it with water and let it set overnight to ensure there are no leaks before putting any hazardous substance in it.