ZUCCHINI: the irrepressible squash

It's often harder to get rid of the offspring of a backyard zucchini than to give away a litter of kittens. Even the nicest people resort to the most devious means.

''Oh, wait, before you go,'' people have yelled as I've left their house, ''here's a little something from our garden,'' they say breathlessly as they hoist a sack into the trunk of my car.

There may be a welcome tomato or two dropped in - for color I suspect - but usually it's just a fleet of zucchini the size of Indian war canoes.

The ubiquitous zucchini, however, was not always as well known as it is today. Twenty years ago food writers had to explain that it was indeed edible.

If proof be needed that it has made enormous inroads since then, consider the International Zucchini Festival held each year in Harrisville, N. H. Here, along with awards for recipes using the lovable squash, there appeared a ''zukelele'' in the Best Musical Instrument Made From a Vegetable category. Fortunately, the zucchini is as versatile. It may be sauteed, steamed, boiled, broiled, bake-stuffed, grilled, and steamed. It can be made into soups, salads, and entrees as well as breads, pickles, marmalades, and cakes.

One of the simplest preparations is to cut the zucchini in 1/4-inch slices, dip them into beaten egg, then in flour, and saute in hot oil until golden.

Here are a few of the countless recipes available. Tuna Stuffed Zucchini Boats

3 large or 6 medium zucchini

1 7 1/2-ounce can tuna, drained

1 egg

3 tablespons Parmesan cheese, grated

3 tablespoons chopped parsley

Salt and pepper to taste

1 1/2 cups tomato or spaghetti sauce

1/2 cup buttered bread crumbs

Cut zucchini lengthwise and remove seeds. Parboil zucchini in a large pan of salted water until slighty tender. Test for doneness with skewer.

Combine and mix thoroughly tuna, egg, cheese, parsley, salt, and pepper in bowl.

Stuff zucchini with tuna mixture. Add tomato sauce and top with bread crumbs. Place in greased oven-proof dish, or on cookie sheet on top of crinkled aluminum foil. Bake at 300 degrees F. until heated, about 20 minutes.

The following recipe from ''The Zucchini and Carrot Cookbook,'' by Ruth Conrad Bateman (Ward Ritchie Press, 1976, $4.95) combines tomatoes and zucchini.

Tomato Zucchini Pie

2 cups zucchini, unpeeled and cut in 1/8-inch slices

1 small onion, thinly sliced

2 tablespoons olive or vegetable oil

1 to 2 tomatoes, cut in 1/3-inch slices

1 tube (8 ounces) refrigerated crescent rolls

2 tablespoons dry bread crumbs

Salt and pepper

1/2 teaspoon oregano

1 1/2 tablespoons butter

Flour

2 eggs, beaten

1 cup milk

1/4 cup shredded Swiss cheese

1/4 cup grated Parmesan cheese

Saute zucchini and onion in oil until onion is soft and zucchini is slightly brown.

Blot tomatoes on paper towels.

Unroll crescent rolls, lay on board, and arrange in shape to fit into 9-inch glass pie pan.

Lay rolls in pan and press edges together to form crust on bottom and on sides. Sprinkle with bread crumbs and cover with zucchini and onions.

Season with salt, pepper, and oregano.

Heat butter in same frying pan, dip tomato slices in flour, and fry until slightly soft. Lay tomatoes over zucchini.

Beat eggs with milk and season lightly with salt and pepper. Pour over vegetables. Sprinkle top with cheeses.

Bake at 350 degrees F. 40 to 45 minutes or until filling is set and crust is browned. Lemon Zucchini Pickles

6 medium zucchii, unpeeled and sliced thinly

1 medium green bell pepper, finely chopped

1 medium onion, finely chopped

1 tablespoon salt

2 teaspoons celery seed

3/4 cup sugar

1/2 cup fresh lemon juice

1 unpeeled lemon, halved lengthwise and thinly sliced

Combine zucchini, green pepper, onion, salt, and celery seed in a large bowl. Mix, and let stand 1 hour.

Dissolve sugar in lemon juice and pour over vegetables. Add lemon slices and mix well. Cover and refrigerate 24 hours. Pickles will keep 3 to 4 weeks refrigerated.