3075 Lane 51 1/2
Manderson, WY 82432
SELECTING GOOD SHRUB SEED
Technique author: Richard Dunne
Purchasing and evaluating seed requires understanding of species peculiarities and pitfalls. This is a general guide for shrub seed evaluation.
Each species has different characteristics for adaptability, shelf life, purity, germination and planting. Seed tests are important in evaluating a seed lot and ocular inspection may detect irregularities requiring further attention.
Description of Seed Characteristics:
Whenever possible select seed of northern, locally adapted ecotypes. Yellow-tagged, Source Identified seed is becoming available and is your best guarantee that the origin is correctly stated. Although some species are not site specific, the best choice is within your geographic area and elevation. Ask vendor what year the seed was harvested; the older the seed, the more frequently the seed should be regermed. Seed collected in November and germinated in December or January will have a test that will carry it through the following fall. Beyond that time the buyer should insist on seed tests no older than three months to assure it is still viable. Sage is usually tested by Tetrazolium (TZ). A good purity is 12% or better. A good TZ is 65% or better. As with all range-collected shrub seed, purity and TZ may be much lower in drought-year crops. Poor test results during good crop years my be a sign of a "troubled" seed lot. Sow on the soil surface. As with most surface shrub seedings, late fall or early spring seeding capitalizes on snow melt to create conditions favorable for germination.
When purchasing sagebrush seed look for the following warning signs:
1. Stale, musty smell may indicate seed is not new crop.
2. Seed rubbed out of its pericarp or inert material ground very fine may indicated over processing and heat or mechanical damage.
3. Less expensive basin big sage is sometimes passed off as SILVER SAGE, which has a much larger seed and a different smell. There should be no trident leaves in a bag of silver sage, which as smooth-tipped leaves.
Northern adapted ecotypes are now coming onto the market as yellow-tagged, Source- Identified seed. Expect more resistance to winterkill and greater ability to regenerate. Avoid New Mexico or Arizona ecotypes whenever possible. Expect Utah, Colorado, and Wyoming ecotypes to be more expensive and frequently unavailable. Seed stores well; 12-month tests are adequate. Usually tested by Tetrazolium, which is more indicative of viability than mere utricle filll. A good purity is 95%; a good TZ is 40%. Should be drill seeded 1/2 inch deep.
When purchasing fourwing seed look for the following warning signs:
1. Some seed from New Mexico and southern Utah has been known be infested with Field Bindweed or Wild Morningglory (Convolvulus arvensis).
2.Watch for broken utricles as a sign of overprocessing.
3.Watch for greyed or discolored seed. May indicate post-harvest drying problem.
4. Native fourwing rarely tests over 70% viable by TZ; question a higher TZ.
Northern adapted ecotypes not likely to be available for several years. Most seed originates in New Mexico or Arizona as Sonoran Desert transition ecotypes. Expect chronic shortages as greater demand chases available seed. "Hatch" is a selected cultivar from a Utah ecotype.
Seed storage life is one to two years. Beyond September of year following collection, buyer should insist on 3 months tests. Usually tested by Tetrazolium. A good purity would be 70%; a good TZ would be 55%. Sow on soil surface.
When purchasing winterfat seed look for the following warning signs:
1. Yellowing fluff on the seed may indicate age, improper drying, or premature collection.
2. Utricle breakage reduces viability and storage life significantly. There will be some breakage in all lots but more than 10% should be cause for further scrutiny.
Rabbitbrush seems to be more amenable to being moved than other shrub species. Any source from a neighboring state is probably adequate. Usually readily available. Often very poor storage life with significant loss of viability possible at any time and with high likelihood of serious viability loss within one year of collection. Purity as high as 50% but usually about 20%. A good TZ would be 65% or better. Broadcast on the soil surface.
When purchasing rabbitbrush seed look for the following warning signs:
1. Broken seed indicates overprocessing. Remaining seed may be microscopically cracked.
2. Yellowing of inert material (fuzz) may indicate aging.
3. Good seed should snap when bent; unfilled seed bends without snapping.
Ecotype sensitivity poorly understood. Select nearest origin when possible. Shelf-life one to two years. Purity 40% to 60% to be expected. TZ above 40% acceptable. May be drill seeded to a shallow depth.
When purchasing greasewood seed look for the following warning signs:
1. Broken utricles or excessively rubbed wings may indicate processing damage.
2. Holes in utricle sides are signs of insect damage. If your seed is labeled as 60% TZ but 50% of utricles have holes you may have mislabeled seed.
WYOMING'S ONLY NATIVE SEED COMPANY