The fact that there is a grass famine in Detroit is not news to local smokers.

It appears, however, that the phenomenon is nation wide with reports received of similar situations in New York, Chicago, and San Francisco.

The causes, although speculative, appear to be two-fold. The first holds that the Mafia has completely stopped large shipments of marijuana into the country in an effort to drive independent dealers out of business and bring the entire scene back under their control.

The second reason is that the Mexican and American governments are escalating a war against marijuana. Recently, narcotics officials from both countries met in Mexico City. They were told about a new kind of chemical warfare.

According to the United Press, a new substance has been discovered that can be sprayed on pot patches from helicopters. The make-up of the substance is classified, but a law enforcement official said it is so foul tasting that it makes grass unsmokeable.

The few hardy souls who can tolerate the taste will find that two puffs produce uncontrollable vomiting.

The United States has offered the Mexican government the use of new instruments which can be used to detect fields of pot from the air. These devices could also be used at border stations to catch smugglers.

The marijuana growers have launched a counter-offensive with technological advances of their own. They use fertilizers to grow bigger plants in less time. They then compress the dried plants, using hydraulic presses made from commercial auto jacks.

These presses turn out bundles which take up only a quarter of the space needed for the hand packaged ones, making border-crossing easier on the smuggler.