Fall Seeds

Autumn is a busy time at the Ecology Center with the staff collecting and cleaning seeds for planting in the spring. Before we discuss the process of collecting and cleaning, let's talk a little about seeds in general.

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After a plant is fertilized, the egg cell divides many times to form the embryo, or the baby plant. The plant embryo forms a hard wall around itself and this is known as a seed coat. Within the seed is the endosperm, which provides food to the developing embryo. The cotyledons within the seed provide a similar function. These are the seed leaves and they also contain food for the developing plant. The seed coat houses the embryo and is able to withstand extreme temperatures, fire, snow and ice, abundant rainfall or dry spells. The seed coat also protects the embryo from abrasive material found in the soil, and passage through the digestive system of animal.


A newly formed seed may require days, weeks, months, or even years to fully mature and requires the correct soil temperature, moisture, humidity and length of daylight to germinate.

Although some plants drop seeds at their bases, most are dispersed through a variety of methods. Some seeds are designed to be lifted and carried on the wind; Maple trees, Milkweeds and Thistles take advantage of the wind.

Swamp Milkweed seeds are dispersed on the wind.

There are other seeds with barbs, bristles, tiny hooks and hairs that latch on to the fur of a passing animal or human clothing. Beggar's ticks (Bidens sp), Cockleburs, and Burdock (Arctium lappa) are a few examples of these sticky seeds.

Seeds attached to the author's pants.

Some animals, such as birds, eat seeds which are later distributed after the animal defecates. Some of these tasty seeds include Poison Ivy, Mulberries, Pokeweed and Japanese Honeysuckle.

Goldfinches love (and disperse) Purple Coneflower seeds

Seed cleaning may bring images to mind of scrubbing seeds with soap and water, but this is not the case. Seed cleaning is essentially separating the seeds from the chaff and spreading them out to dry. Ideally, colanders, sieves, window screens or other forms of metal screens are ideal for this step, but space and cost is something of an issue for us. We (or willing students) separate the seeds from the chaff on top of a white piece of paper or tray before moving the seed to another tray.

The newly separated seeds can be dried in paper or plastic bags (open for air circulation), dixie cups or spread out on small plates. The seeds need to be turned or stirred every few days to make sure they are dried evenly. Once dried, the seeds can be stored in a cool place (usually the refrigerator) out of direct sunlight until they are ready to be planted.

Glossary

Chaff: the outer material on a plant, such as the seed coat, dried flowers, leaves and other scaly material.

Germination: the process in which an inactive seed begins to sprout and grow into a seedling under the right conditions.