Mindi Grell, age 7, of Galva, Iowa, for her question:
WHAT ARE SOME MODERN USES FOR SEAWEED?
When Columbus made his first voygae to America in 1492, his ships passed through great masses of seaweed. The weeds were brown algae, also known as gulfweeds. Great masses of the weeds can be found floating in the Atlantic Ocean east of Florida. The plants have small air bladders, shaped like berries, which make it possible for the weeds to float on water.
Any plant that grows in the sea can correctly be called a seaweed. When a botanist speaks of seaweed, however, he is usually referring to one of the larger brown or red algae. These seaweeds are related to the green pond scums of stagnant water, but not of the higher water plants.
Most of the seaweeds found in the cold ocean waters are brown algae while most of the plants growing in the seas of tropical areas are red algae.
Giant kelps of the Pacific Ocean are a type of brown alga. The stems of these great collections of weeds often grow more than 200 feet long.
During World War I, giant kelp of the Pacific was harvested to make fertilizers and explosives. Chemists now extract great amounts of iodine and algin from kelps. Algin is a product that has many commercial uses because it can hold several liquids together.
Algin finds its way into our dining room. The useful product which is made from kelp is used in ice cream because it will keep the water in milk from forming crystals. It is also used in salad dressings, chocolate milk and other foods.
Algin is also used in making aspirin and other drug products. Irish moss, or carrageen, is the name of another type of seaweed that can be found in rocky places of the ocean off Great Britain, Ireland and the eastern coast of North America. The most common type of Irish moss is a reddish brown or purple variety that has forked, fan shaped fronds. The seaweed is prepared and then used commercially in a number of different soups and desserts.
Kelp is an alkaline ash made by burning certain types of seaweeds which are also called kelp. The ash is a source of iodine. Kelp is about 20 to 25 percent potassium chloride. It also contains large amounts of common salt, sodium carbonate, sodium and potassium or sodium iodide.
Partially dried kelp is also used as fertilizer. In addition, the dried plants, ground fine, are sometimes used as body conditioners since they have many minerals and vitamins.
Large masses of giant kelp grow in the waters off the Pacific coasts of North America and South America. It can also be found growing off the coasts of Ireland, Scotland and Brittany.