A study that planted 474 trees and measured their growth characteristics for more than a year. Logistic regression was used to evaluate whether tree height, elevation above the river channel, distance to existing cottonwood or coyote willow, soil conductivity, soil texture, planting depth, planting method (mechanical auger vs. hand-digging), and provision of natural and commercial supplements affected survival probability. The authors found that survival probability was greater in auger-dug than hand-dug holes and increased with elevation above the river channel bottom. Survival was lower in sandier soils and in soils with higher salinity.

Laub, B.G., Detlor, J. and Keller, D.L. (2020), Determining factors of cottonwood planting survival in a desert river restoration project. Restor Ecol, 28: A24-A34. https://doi.org/10.1111/rec.13086