Artificial Regeneration (Planting and Direct Seeding)

Artificial Regeneration (Planting and Direct Seeding) • Why use artificial regeneration • no natural seed source • change species composition • genetic improvement • control density/spacing • control time and duration of establishment period • repeatable in event of failure

Artificial Regeneration (Planting and Direct Seeding) • Cost • Tends to be high • Makes biological (as opposed to financial) sense only when natural regeneration would likely fail • Important considerations include species selection and genetics

Species selection • Choose species suitable for your objectives • growth rates • wood characteristics • wildlife characteristics (e.g. mast production) • Choose species adapted to the site (wet? dry?) • Well adapted species grow better and tend to have fewer health problems • May use a mixed species plantation due to • multiple objectives • changing site conditions across planting area • to take advantage of differing growth rates or form • Do not plant a species outside its natural range unless it has been tested

Genetic considerations (for a specific species) • Use seeds or seedlings from a tree improvement program whenever feasible and available • Verify traits you desire were selected for: • growth rate • straightness • small branch size, large branch angle, small crown size (wood quality issues) • disease resistance • high wood specific gravity • drought resistance • cold hardiness

Genetic considerations (for a specific species) • If improved seedlings or seeds are not available, use geographic seed source selection (provenance) • In a restricted geographic area, individuals in a species tend to have similar genetic traits • Be careful when moving seed source more than 100 miles north or south • If unsure, use a local seed source

Planting Forest Tree Seedlings • In the central and southern US, bare-root seedlings are typically planted • Mostly 1-0 planting stock is used in the Central Hardwood Region • "1-0" refers to: # seasons in nursery bed - # seasons in transplant bed • 1-1 and 2-0 seedlings are used in the North and West for some species

We generally want to plant the largest and best developed seedling that will survive given the outplanting conditions…and that can be handled efficiently and economically. The traits of a high quality seedling change depending on the site and planting circumstances. Seedling Quality

Seedling Quality • Root collar diameter (caliper) is the most useful single indicator (for undamaged seedlings) • Oaks should be larger 3/16” basal diameter • Smaller seedlings should be culled • Larger root mass (not length, due to planting problems) and more lateral roots (5+) are better, while a lower shoot/root ratio is better • Hardwood seedlings should be at least 18" to 24" tall • Bare-root seedlings should: • Be dormant before lifting (have winter buds) • Have met minimum chilling requirements in the nursery if they are to be stored before planting

Containerized seedlings • Containerized seedlings: grown in individual containers • Advantages: • Extend planting season • shorten production time • Usually increased survival on adverse sites • Lower risk of transplant shock • Often increased performance (growth) • Disadvantages: • Usually costs more • Containers are more difficult to handle than bare-root seedlings

Containerized Seedlings

Nursery practices used to influence seedling quality • seed source • seedbed density • control insects and disease • control competition • irrigate and fertilize • inoculate with mycorrhizae • top prune • root prune or wrench

Proper Care of Seedlings In Storage: • Keep cold - 33-40°F (do not freeze); bales should have high humidity (85-95%) • Pack roots in a moist medium (e.g., peat moss), or dip in kaolin clay or a gel • Water regularly (weekly), if in bales • not needed if in sealed K-P bags, in wax coated boxes, or if they have a root coating) • Provide good air circulation - store on racks, no more than two bales or bags high, four boxes high • Do not store non-"dormant" bare-root seedlings (should meet minimum chilling requirements) • Keep storage as short as possible--avoid storage longer than 8 weeks (4-6 weeks if not in cooler); no more than 4 weeks, if in sealed bags or boxes

Proper Care of Seedlings In Transport: • Refrigerated trucks are best • Slat-sided trucks covered with a tarp and with back open acceptable in cool weather: night transport may be needed in warmer weather • Keep temperature in bags or bales below 50 F (good air circulation) • Put on racks or shelves - do not pile more than two high, unless in boxes

Proper Care of Seedlings At the Planting Site: • Deliver only one day's supply to each planting site • Protect seedlings from sun and wind • keep in insulated or refrigerated trailer or truck, if possible, otherwise in shade • Avoid freezing • Do not expose bare roots for more than 10 minutes, 5 minutes if temperature >70 F • Keep seedlings in planting bags or containers as long as possible • Keep planting bags watered

Proper Care of Seedlings During Planting: • Postpone planting if: low soil moisture; hot, dry, windy weather; below freezing temperatures • Plant as deep or deeper than seedling grew in nursery • 2-3" deeper OK, as long as the tip is not covered • Plant deeper on dry sites (do not bury tip) • Avoid field root pruning • Planters should not carry more than one seedling in the hand at one time

Proper Care of Seedlings During Planting: • Avoid U or J-rooting • planting hole/furrow must be deep enough • Do not leave roots exposed • Pack soil around roots • A supervisor should check for: root stripping, discarded seedlings, correct spacing, proper soil packing, shallow planting, J-rooting • For containerized seedlings: be sure to cover the top of the plug with soil to prevent desiccation

Planting Methods • Advantages of Machine (vs Hand) Planting: • Faster, more efficient (especially on large tracts) • More consistent high quality results, especially with large seedlings • Better root environment in heavy soils • Advantages of Hand (vs Machine) Planting: • More efficient on small tracts • Less restricted in rough or steep terrain • Less intensive site preparation is necessary • Low capital investment in equipment • Less erosion potential (machine planting must be on contour)

Hoedad Containerized Seedling Dibble Dibble Bars Tree Planting Hand Tools Power Auger

Machine Tree Planting

Planting Practices • Planting in the central hardwood region • Hardwood tree seedlings are best planted when seedlings are dormant and the ground has thawed • Timing: March to May • A cool (35 to 60 F) overcast day with little or now wind is an ideal planting day • Spacing • Generally 8 x 8 ft (681 tpa) or 10 x 10 (436 tpa) foot spacing recommended for hardwood plantings

Underplanting • Underplanting is the establishment of nursery grow tree seedlings under an existing forest canopy • Purpose: • Supplement natural advance reproduction • Establish high-value species

Underplanting • Field performance linked to: 1) initial seedling size; and 2) understory growth conditions • Usually coincides with silvicultural treatments like midstory removal or shelterwood harvest • Understory competition control may enhance survival and growth • As with natural seedlings of species reliant on advance reproduction, underplanted seedlings must be allowed to develop to sufficient size in order to be competitive following final overstory removal.

Direct Seeding • Direct seeding is the process of establishing tree plantings by the used of seed instead of seedlings • Direct seeding is rarely used in the central hardwood region for establishing hardwood plantation • Direct seeding has been used along with soil scarification operations to successful establish oak advance reproduction in shelterwood systems

Direct Seeding • Steps to successful direct seeding operation • Plan ahead to minimize poor germination seed or seeding failure • Obtain adequate amounts of quality, viable seed from an appropriate source and prepare it for sowing • Match species to site • Determine the proper sowing rates for desired density and spacing • Select an appropriate method for dispersing the seed • Have a follow-up plan if sowing yields too many or too few seedlings

Direct Seeding • Advantages • Planting season for direct seeding is longer than for seedling planting • Less labor intensive • Allows seedlings to become established in the soil with their root systems developing naturally • Roots of planted seedlings are susceptible to damage and transplanting shock

Direct Seeding • Disadvantages • More seed per acre is required to obtain the desired number of seedlings • Delayed seed germination, slower rates of development, and loss of seed to predation and drought may lengthen the time to seedling establishment (or cause complete failure) when compare to planting. • Lack of control over seedling density and unfavorable conditions during the germination process • Site preparation must break and mix the seedbed • Inefficient use of high-value and genetically improved seed • Stands have irregular spacing and arrangement

Direct Seeding Practices • Timing: • By direct seeding in the fall, the natural stratification process (moist, cold temperatures) breaks seed dormancy and promotes rapid germination in the spring • Predation losses with fall planting are higher • If direct seeding planned for late winter or early spring, proper seed storage and seed preparation (pre-germination stratification treatment) must be observed • Seed storage and preparation depending on species

Direct Seeding Practices • Depth of sowing • Depth of sowing is dependant upon the species, seeding method, and predation pressure • Generally, the depth for sowing is 2 times the diameter of the seed • Planting too shallow increases losses to predators and drought, planting too deep can delay germination • Seeding rates • 1 pound per acre for loblolly pine • 18,200 seeds per acre • 24 to 36 pounds per acre for northern red oak • 3000 to 4500 seeds per acre • 75 to 112 pounds per acre for black walnut • 3,000 to 4,840 seeds per acre

Direct Seeding Approaches and Methods • Approaches of direct seeding • Broadcast seeding • Spot seeding • Drilling • sowing in rows like an agricultural crop • Methods of disseminating seeds • Hand sowing • Machine sowing • Aerial seeding

Planning an Artificial Regeneration Operation

Site Preparation for Hardwood Plantings

Post-Planting Maintenance • Second and possibly third year pre-emergent herbicides should be sprayed in planting strips or spots where the ground is bare and herbicides can adequately contact soil • Overtop sprays of grass herbicides and directed sprays for broadleaf control can be administered during the first through third years as needed • Mowing should be used in combination with herbicide applications or by itself to control weed competition that becomes established between rows.

Post-Planting Maintenance Mowing • Mowing should be considered when competition control treatments fail to provide adequate weed control • Mowing should only be used to: • Prevent seed development of invasive or problematic weed species • Prevent development of weeds that have the potential to grow above 4 to 5 feet and occupy a significant portion of the planting site • Provide access for cultural control of weeds and rescue treatments in planting rows or spots

Post-Planting Maintenance More on Mowing • Mowing to control residual competing vegetation increases the probability of physical damage to seedlings from mowing equipment, especially if mowing occurs many times during the growing season for several growing seasons • Mowing should be discouraged and is one of the more ineffective methods to control competitors near planted seedlings

Post-Planting Rescue Treatments Established tree plantings with vine, tree, and shrub competition • If problematic vines are present, either in the row or between rows, they should be controlled • Vines in rows can easily wrap around the planted seedlings, especially if significant tree, shrub or large herbaceous weeds are present • Problematic vines such as trumpet creeper, morning glory, honeysuckle or poison ivy, the planting should be treated as soon as possible • The best control can be achieved by: • Mowing between rows directly after full leaf-out • Once new shoots emerge from the root systems and stumps, spray new foliage with a post-emergent, broad-spectrum herbicide at the end of the growing season

Post-Planting Rescue Treatments Established tree plantings with vine, tree, and shrub competition • Cutting of trees, shrubs and vines directly adjacent to seedlings is sometimes required especially when competing vegetation is large • Treatment should be combined with a cut-stump herbicide treatment to reduce or eliminate sprouting • Basal sprays can be used on individual woody plants growing around seedlings • Make sure that the basal herbicide spray does not get on the planted seedling

Post-Planting Rescue Treatments Established tree plantings with broadleaf herbaceous weeds • The planting should be surveyed to determine if trees are fully overtopped or will be overtopped by herbaceous weeds. • If the trees are fully overtopped: • Overspray the entire planting with a broad spectrum, post-emergent herbicide • Proper application rates are critical to minimize drip onto seedlings. Large drop size and low pressures are needed to ensure penetration • Use directed sprays of post-emergent herbicides around the seedlings to further reduce competing species • In conjunction with the post-emergent sprays, one application of pre-emergent herbicide should be applied in the rows prior to the growing season

Artificial Regeneration (Planting and Direct Seeding)