Contact the area forestry office drop-off location in your area before collecting for the quota of cone or seeds they will purchase plus instructions on proper collecting, handling, and labeling requirements. Collecting, storing, and delivering large quantities of high-quality seed, you are helping to grow deciduous forest adapted to Minnesota.
| Species | Seed crop freq. (years) | Time to collect seed | Shape and app. | Collection method* | Cleaning | Storage until seeded in fall | Comments |
|---|---|---|---|---|---|---|---|
| Black ash | 1–3 | October to December | Flat exclamation point | H, T/S, P | Remove stems and leaves | Keep dry—can be stored in feed sacks in a 40°F cooler for several weeks | Can hang on trees bunches into December |
| White ash | 3–5 | Late September to late November | Flat exclamation point | H, T/S, P | Remove stems and leaves | Same as above | Hard to tell from green ash; purple leaves only sure way |
| Green ash | 1 | October to January | Flat exclamation point | H, T/S, P | Remove stems and leaves | Same as above | Grows on a wide range of sites |
| Basswood | 1+ | September to December | Brown peas with a propeller on a stalk | Rake, T/S, H | Crush stems and wings, separate hard, round seed | Dry—store in a moisture-proof container at 40°F or lower | Second-year germination; needs a cold/warm/cold cycle. |
| Black cherry | 1–5 | August to September | Purple-black berries | Rake, T/S, H | Mixed soft fruit, separate hard seed, dry | Dry—store in a moisture-proof container at 40°F | Collect from high-quality trees |
| Hackberry | October to December | Purple-black berries | Rake, T/S, H | None | Store dried fruits or cleaned seeds in a moisture-proof container at 40°F | ||
| Shagbark hickory | 1–3 | September to December | Four football-shaped segments together | H, Rake | Remove leaves and twigs | Can be stored in feed bags at 40°F | Stay within the natural range |
| Silver maple | 1 | June | Green to brown propellers | Rake | Remove stems and leaves | Plant as soon as possible in early summer | Seed shallow |
| Sugar maple | 3–5 | Late September to early November | Green to brown propellers | Rake, T/S, H | Remove stems and leaves | Dry—store in small seed sacks at 40°F | One bushel per person per day is the maximum yield for handpicking |
| Bur oak | 2–3 | August to September | Acorn almost fully covered by a cap, which has a furry fringe | Rake, B-A-N, Pick | Cut open a handful to test for viability; hand sort | Only for a few weeks at 40°F— soak overnight before storage | Race with squirrels and deer for acorns |
| Red oak | 3–5 | September to early October | Reddish-brown acorn | Rake, B-A-N, Pick | Float, then remove "floaters" or hand sort | Only for a few weeks at 40°F— soak overnight, sow in fall | Race with squirrels and deer for acorns |
| White oak | 4–10 | Late August to September | Tan to light-brown acorn, thinner and smaller than most red oak acorns | Rake, B-A-N, Pick | Float, then remove "floaters" or hand sort | Only for a few weeks at 40°F— soak overnight, sow in fall | Race with squirrels and deer for acorns |
| Black walnut | 1–2 | October | Golf ball-size nut with green to black husk | Rake, B-A-N, Pick | Remove leaves and twigs | Only for a few weeks—small piles to prevent the heating of seed | Stay within the natural range. Do not store walnuts in gunny sacks |
| Gray dogwood | 1 | July to August | Pea-sized white berries in clusters | H | Remove leaves and twigs | Seed extraction from the fruit is not necessary | Sow in fall as soon as possible after collection |
| Red-osier dogwood | 1 | July to September | Pea-sized white berries in clusters | H | Remove leaves and twigs | Seed extraction from the fruit is not necessary— prevent heating of seed | Sow in fall as soon as possible after collection |
| Chokecherry | 1–2 | August to September | Pea-sized dark red to purple berries | H | Remove leaves and twigs | Seed extraction from the fruit is not necessary—surface dry fruit is OK for sowing. | Sow in fall as soon as possible after collection; Prevent heating in storage. |
| Highbush cranberry | 1–2 | August to September | Pea-sized bright red berries in clusters | H | Remove leaves and twigs | Seed extraction from fruit helpful is in some Viburnum species | Often second-year germination; Prevent heating in storage. |
*Collection methods:
H – Handpick from cuts or standing trees
T/S – Tarp ground and shake branches when the seed is ready to fall
P – Pruning hook on a long pole
B-A-N – Bag-a-Nut machine
Rake – Rake fallen seed from street or lawns
Pick – Gather fallen seed by hand from the ground
Bagging seed for shipping
- Oak seeds—put into breathable, woven poly bags or burlap.
- Ash and maple seed—put into paper or burlap bags after drying.
- Walnuts—keep in small, open containers or small piles.
Label all bags with species, date, and place collected. Do not overfill bags.