Lichens make interesting collections for children who spend time at summer camps. These, too, should be studied through a magnifying glass in order that the sometimes weird, sometimes lovely, structures may be appreciated. One expert estimates that an amateur should be able to collect from fifty to one hundred different kinds of lichens in many sections of the East (some ten thousand species are known to botanists). Lichens are a joy to the collector because after they are dry and brittle they will return to their original forms when soaked in water.
Mosses are a companion collection to lichens. They are a slightly higher order of plant lif e and number almost twenty thousand species. Some of them are strangely beautiful. The leaves of branching varieties often resemble ferns, ostrich plumes and even tiny palm trees. Again, for thorough appreciation, these should be studied through a magnifying glass. Like the lichens they will also revive from the dry state when soaked in water.
Very helpful material for the collector of both lichens and mosses is contained in the book Plants by Herbert S. Zim. Serious students may find more technical books desirable later on, but this book contains a world of easily assimilated information for the beginner.
Pressed weeds. No collection could be easier to assemble, and no study more profitable for potential or working gardeners. A weed, of course, is no special kind of plant, but simply any uncultivated plant that grows where it isn't wanted. In short, it is an intruder and a pest.
Many weeds have real intrinsic beauty and would be cultivated if they had civilized manners and hadn't propagated with such abandon. Surely the pestiferous dandelion, with its sunny charm, would be much sought after if it were rare and had to be catered to and coaxed to grow.
Since weeds are one of man's big problems in cultivating the land, and since they usually make faster early growth than planted crops, it behooves every gardener, no matter how
young, to be able to recognize them when they invade his patch of ground.
The most important time to recognize weeds, of course, is in their very early stages. This is the danger period when amateurs are most likely to confuse them with their own seedlings. Small wild plants often have a disturbing resemblance to tame ones, and seem to have a penchant for popping up beside them.
It would be very worth while, therefore, to have a group of gardening youngsters collect and press all the local weeds they can find-picking them in the third-leaf stage. Mounted on ordinary filing cards they would form a useful, compact and comprehensive herbarium.
Cards with specimens attached by a few spots of transparent cement may be slipped into cellophane envelopes.