University of Arizona “Bear Down”
Organic Land Stewardship Program

Using Science to Transform Arid Soils

Watch our video about the program

» Download the UA Case Study (PDF)

The early success of a pilot Merlin Organics program in 2011 prompted The University of Arizona to expand their “Bear Down” Organic Land Stewardship Program to encompass the University’s entire Mall in 2012. The program is the largest of its kind at a public university in the U.S., covering more than 10 acres of trees and turf in of one of the University’s most important and graceful corridors.


Merlin Organics had been working for two years with Dr. Martha Hawes, a professor and plant pathologist in The University of Arizona’s College of Agriculture, on scientific trials that involved treating a crop pathogen with our actively aerated compost tea. Based on the results of our research and field work, in early summer of 2011 we approached the University’s Facilities Management Team about a prospective project on the Mall.

UA Bear Down PlotsThe Challenge

As a pilot project with an eye toward an expanded program, The University of Arizona’s Facilities Management team charged Merlin Organics with restoring turf health in an area in the heart of campus, including a section of lawn that was described by the client as “the worst plot on campus.”

The project placed three plots totaling 0.3 acres in front of Bear Down Gym and the Science & Engineering Library under 100% organic management.

UA Bear Down Gym PlotBefore

The barren Bear Down Gym plot had served as a staging area for a construction project, and the University had spent almost a year trying to restore it with conventional methods. Two adjacent pilot plots, though less damaged, nevertheless suffered from nutrient deficiencies, poor soil structure, and inadequate microbiological activity.

UA Bear Down PlotsAnalysis

Merlin Organics’ analysis included remediation of soil structure damage and restoration of biological diversity. Based on its analysis, Merlin designed a one-year program that began two weeks after engagement.

First granular applicationJuly 14, 2011

After a deep core aeration, Merlin applies an initial pre-treatment of granular organic amendments to prepare the soil for liquid treatments.

First liquid applicationJuly 21

The first application of Merlin’s liquid biological solution is applied. Monsoon rains had already begun breaking down the granular amendments to “green up” the plots.

100 hours after first applicationJuly 25

A mere four days after the initial liquid application, marked improvements in turf color and texture are observed.

Root measurementsSeptember 15

After just two months of treatment, the program has already generated better than expected results. Root-feeding nematodes have nearly disappeared, replaced by beneficials. The soil’s dry weight, an important measure of its water-holding capacity, has improved to within target range. And most significantly, nutrient cycling is being restored at a better than projected rate.

UA approves program expansionUA Approves Program Expansion

The pilot program had a planned duration of one year, but based on the early results, after just six months the University of Arizona Facilities Management team approves expansion of the program to encompass the entire Mall.