Aerial seeding
[2] Aerial seeding may quickly and effectively reduce erosion hazards and suppress growth of invasive plant species.
[3] Problems with direct broadcast include germination, pests and seed predation by rodents or other wild animals.
Lt. John A. Macready, a U.S. Army pilot, used a modified Curtis JN-6 to dust a field of catapla trees with arsenate to kill sphinx moth larvae.
[9] Surplus planes from World War II were initially used for aerial seeding, with the open cockpit Stearman biplane used frequently.
[9] In 1987, Lynn Garrison proposed the creation of a Haitian Aerial Reforestation Project (HARP), by which tons of seed would be scattered from specially modified aircraft.
[14] Given the focus of this company on disaster relief, they have considered sapling darts not to be an effective solution since "nursery suppliers lack capacity to reforest after sizeable wildfires — especially repeat fires.
[15] Saplings would be encased in sturdy and biodegradable containers which would work as projectiles and pierce the ground at high velocity.
This project was being developed in 1999 by a company called Aerial Reforestation Inc, in Newton, Massachusetts, based on an original idea by pilot Jack Walters.
[17] Other researchers are still investigating the potential of these "aerial sapling darts", by improving their aerodynamics to achieve better soil penetration and therefore higher reforestation yields.
Adequate soil moisture for germination and establishment of seed requires that the top 0.5 -1 inch be moist.
[4] Dropping seed balls from crop spraying aircraft is the most common method and the one practiced by Farmland Aviation, Kenya, one of the few companies active in this field.
Low-cost UAVs lacked payload capacity and range limits them for most aerial seeding applications.
Despite its low yield, interest in aerial seeding has recently grown, while searching for a quick system to obtain reforestation and fight global warming.
Aerial seeding is therefore best suited to sites whose remoteness, ruggedness, inaccessibility, or sparse population make seedling planting difficult.
It is particularly appropriate for "protection forests" because helicopters or planes can easily spread seed over steep slopes or remote watersheds and isolated dryland areas.
It has the potential to help increase production of tree crops for forage, food, and honey as well as wood for fuel, posts, lumber, charcoal and pulp.
To germinate successfully, seeds usually must fall directly onto mineral soil rather than onto established vegetation or undecomposed organic matter.
The native trees (such as species of Acacia, and other genera) in these areas are generally well adapted for survival under difficult field conditions.
As a prerequisite to any method of reforestation, the species selected must be adapted to the temperature, length of growing season, rainfall, humidity, photoperiod, and other environmental features of the area.
Ideally, before aerial seeding takes place trial plots should be established to test those species most likely to germinate and grow successfully on the chosen sites.
Aerial seeding may prove to work best with "pioneer" species, which germinate rapidly on open sites, are adapted for growth on bare or disturbed areas, and grow well in direct sunlight.
