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Look here for definitions of the headings used for each vegetable.

PLANT: The separation distance between plants necessary for successful seed production is given under this heading for each vegetable. Techniques to prevent cross-pollination other than by separation distance are also suggested.

Caging is a separation technique where insects that might cause cross-pollination are prevented from reaching flowers by a fine net supported by wire or wood. If flowers in the cage are not self-pollinating, several plants must be included in the cage and pollinating insects introduced. Alternate day caging allows two plants or two groups of plants to be naturally pollinated by insects. Unwanted cross -pollination is prevented because one plant or group of plants is caged one day and the other plant or group is caged the next.

Root to seed describes a technique used to produce seed for biennial crops. The roots of the biennials are harvested in the fall, trimmed and stored for the winter. The following spring, the best roots are planted for seed production that season. When roots to biennials are left in the ground in the fall to produce seeds the following summer, the term seed to seed is used.

FLOWER: A complete description of each vegetable's flower type and pollination method is given.

INBREEDING DEPRESSION: This section alerts gardeners to the possibility of a loss of vigor because of inbreeding. Vigor is a desirable characteristic that describes strong, vibrant germination and plant growth. Inbreeding can result from self-pollination or pollination between a small number of close relatives. Some vegetables show no signs of inbreeding depression even when self-pollinated for many generations and others show signs of inbreeding depression in first genera tion offspring.

SELECTION TRAITS: In the interest of clarity we make a distinction between selection characteristics and selection traits.

Characteristics are general features attributed to unidentified complexes of genes. Complex and hard to define, characteristics are often ignored by commercial breeders and offer the most rewards for home gardeners. Characteristics on the priority list at ISSI include but are not limited to freeze tolerance, cold tolerance, regional adaptability, winter hardiness, early maturation, vigor and flavor. Each home gardener can create his or her own list of selection characteristics.

Traits are specific features traceable to identifiable genes. For example, pea traits traceable to single genes include vine growth (bush or tall), seed texture (smooth or wrinkled) and disease resistance (fusarium, enation mosaic and powdery mildew resistance).

Dominant trait, abbreviated "D", is the variation of a specific gene that results in observable traits. For example, in bachelor's buttons blue is the dominant color. Seed harvested from multi-colored stands that have been allowed to cross-pollinate is likely to produce plants with a majority of blue flowers.

Recessive trait, abbreviated "r", is variation of a specific gene that results in observable traits only if the dominant variation is not present. For example, wrinkled pea seeds only result when the dominant, smooth-seed trait is missing.

HARVEST: Successful production of seeds may require a growing season several weeks longer than the successful production of an individual vegetable or flower. Plan accordingly. For example, start plants indoors and design a strategy to allow enough time before frosts for the maturation of seeds.

Viable seeds are seeds that germinate and produce vigorous plants. Seeds should not be harvested before they have matured enough to be viable.

Dehiscent seed capsules are open and discharging seeds. Seeds must be harvested before this stage takes place and seeds are lost. Seed capsules in some varieties literally explode at the point of maturity. It is not uncommon to have only a few capsules out of hundreds, mature at any one time.

PROCESS: Cleaning and separating seeds from chaff is not difficult or even necessary for small, home garden needs. Often, a little extra time taken during harvest to shake seeds out, one capsule at a time, results in completely clean seeds that need no processing.

Thresh is a term used by seed professionals to describe the process of separating seeds from chaff, small, remaining pieces of pods or coverings.

Flail is the process of fracturing or crushing seed pods in order to free the seeds. This can take the form of everything from simply rubbing broccoli pods between hands to walking over bean vines.

Winnow is an ancient technique used to clean seeds. Seeds and chaff are poured through moving air which blows the lighter chaff aside, allowing the heavier seeds to be collected below.

Cleaning Screens with different-sized openings are used to separate seeds from chaff. The screen number denotes the number of openings that will cover a one inch line. A screen is selected with openings just large enough to let seeds drop through without the chaff or as in the case of larger seeds, a screen selected to allow the chaff to drop through without the seeds. ( See page 36.)

STORAGE: The successful storage of seeds demands cool, dark, and dry condi tions. Put seeds in plastic bags for separation and labeling before putting the plastic bags into air-tight, glass jars to be stored. Note: plastic bags alone do not protect against moisture, especially in potentially moist locations like refrigerators or freezers. Allow jars that have been stored in refrigerator or freezer to warm to room temperature before opening to prevent moist air from condensing on the inside walls of the jar.

Cool: At the National Seed Storage Laboratory in Ft. Collins, Colorado, some seeds are stored at 400° F. below zero. However, generally, storage conditions are adequate if seeds are kept below 50° F.

Dark: Absolute darkness is best. However, seed storage is adequate if direct sunlight or bright, artificial light is avoided.

Dry: Dryness is the most important factor in the long-term storage of seeds. Opti mum levels should be below 9% moisture. Most vegetable and flower seeds will store more than one year without special protection. Silica gel can be purchased for prolonged storage in humid climates.

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