Scientific Studies
Published scientific results from two separate research studies.
Horticultural Research Institute (2000)
A published study from the Horticultural Research Institute in Washington, D.C. showed that transplant shock following the transplanting of large trees can be minimized by applying a combination of selective pruning and irrigation with Treegator Slow Release Watering Bags.
Effect of Transplanting on Water Relations and Canopy Development in Acer (Maple trees) Authors - Amy J. Barton and Christopher S. Walsh, Dept. of Natural Resource Sciences & Ldscp. Architecture - Univ. of Maryland
"During the first 2 weeks of April 1997, 24 field-grown Acer trees (12 Acer truncanum / Trident maple and 12 Acer tataricum ginnala / Amur maple) were transplanted using a 45 inch tree spade. This was prior to leaf emergence.
Trees were moved approximately 492 feet to a blocked study site. Three trees of each Acer species were also left in the original nursery rows as non-transplanted controls.
All trees were irrigated for the three days immediately following their transplant, using Treegator Bags (Original model).
After this initial watering, three trees of each species were randomly assigned to one of four treatments.
Treatments were transplanted control, top pruning, water (provided by Treegator drip irrigation) and water combined with top pruning.
By using a combination of leaf area index and transpiration rates, Acer (maple) trees that were selectively pruned and irrigated with Treegator (Slow Release Watering Bags) exhibited less transplant shock than those that were only pruned or not pruned but were irrigated."
NSY and LDSCP Projects (2001)
A published study by Bert Cregg with Michigan State University Department of Horticulture compared soil moisture, survival and growth of street trees with and without Treegator, as well as compared the incidence of vandalism on Treegator Bags in diverse neighborhoods in Lansing and Detroit, MI.
Influence of post-planting care on street tree performances: Biological and social factors Author - Bert Cregg, Dept. of Hort. and Dept. of Forestry
"In cooperation with the city of Lansing and the Greening of Detroit, we installed Treegator (Bags) on 27 trees in each city. City of Lansing or Greening personnel filled the Treegator Bags periodically through the summer. They also hand-watered 27 trees in each city. In Lansing, 27 trees were not irrigated. In each city, the trees were divided among three neighborhoods and irrigation treatments (Treegator, hand-watered or control) were assigned at random to trees within a neighborhood.
During the summer of 2001, we periodically measured soil moisture at zero to six inches and zero to 12 inches with a TDR soil moisture system. On each measurement run, we noted the presence or absence of the Treegator (Bags) and any evidence of vandalism to the trees or Treegator (Bags).
Irrigation either by hand or using the Treegator (Bags) increased soil moisture compared to the un-watered control trees in Lansing. Between water treatments, there was little difference in soil moisture near the surface, but irrigation with the Treegator (Bags) increase soil moisture deeper in the (soil) profile.
Incidence of vandalism to the Treegator Bags was low. In each city, one of the 27 Treegator Bags installed was removed (2 of 54 total). In Detroit, the one Treegator that was tampered with was moved from a tree in front of a vacant lot to a tree in front of a residence. We did not detect any other evidence of vandalism or tampering.
From the data to date, we conclude that the likelihood of vandalism to Treegator (Bags) is relatively low (less than 4 percent overall) across a range of neighborhoods in Lansing and Detroit. Watering with the Treegator (Bags) can improve soil moisture deeper in the (soil) profile than watering by hand."
