TURFGRASS WATER CONSERVATION ALLIANCE— GROWING INNOVATION FOR MEMBERS
By Jack Karlin
Te Turfgrass Water Conservation Alliance (TWCA) is a 501(c)(3) non-profit organization based in Albany Oregon, the heart of grass seed country. Founded in 2010 by direct competitors in the live goods industry, TWCA is committed to water conservation and dedicated to preserving the ecological benefit of turfgrass in the managed environment.
Membership As a membership based organization no conversation about program identity is complete without an overview of the program membership. Currently, TWCA has 142 members in four countries, thirty-one US states and five Canadian provinces. In addition to ten seed producing companies representing an estimated 85% of the grass seed sold in the US; TWCA members include turfgrass breeders; government officials ranging from local to regional, state, and federal levels; university programs, sod farms, and landscaping companies. TWCA even has individual members who recognize TWCA as a vehicle for positive change.
Three Types of Trialing TWCA utilizes three similar approaches to qualify drought tolerant turfgrasses: chronic drought, acute drought, and low maintenance. While each evaluation looks at turf response to drought stimulus, each one gives a unique look at turf quality and cultivar response to specific conditions.
Te TWCA qualifies drought tolerant turf using independent peer review of objective data collected during multi-year, multi-site trialing. Each trial evaluates a single species of unblended cultivars meaning each trial plot is 100% of a single cultivar. Te TWCA Research Review Committee consists of at least three university researchers who aggregate the TWCA trial results from individual locations over the duration of the trial being evaluated and, based on the statistical analysis of the data, qualify cultivars based on the results. Te geographic range of TWCA’s trialing includes fourteen locations across North America including Olds College and the University of Guelph in Canada and ranges from New Jersey to Oregon and south to Riverside California.
All TWCA trialing is conducted using the copyrighted Turfgrass Water Conservation Protocol (Protocol) as a guiding document. Tis rigorous protocol guides TWCA Research cooperators’ efforts in establishing
52
and maintaining the plots, as well as laying out the turf evaluation methodologies. Te Protocol specifically addresses both chronic and acute drought evaluation.
During chronic drought trialing, the trial plots are allowed to establish, watered to field capacity and then, once trialing is initiated, watered at a predetermined percent of reference ET (ET0
). During chronic stress, digital
image analysis (DIA) is collected at least once a week. Chronic stress trialing is especially useful in determining turf performance during a water restricted period or in areas where the maximum applied water allowance is determined in a regulation.
By far the most common method of evaluation for TWCA is acute drought stress. During acute drought stress trialing, plots are allowed to establish and are irrigated to field capacity after which the water is entirely shut off. Te trials remain in a no water state with digital image analysis (DIA) being collected at least once a week until the top performing grass (the greenest) falls below twenty five percent green cover. Once the top performer falls below 25 percent green, water is reapplied to the trial at a rate of one inch per week. Acute drought stress is excellent for giving a sense of cultivar performance in very dry conditions.
In addition to the Protocol, TWCA also has the TWCA Protocol for Low Maintenance Turfgrass (Low Maintenance Protocol). Copyrighted in 2014, the Low Maintenance Protocol is the first of its kind to detail the maintenance methodologies for evaluating turf performance and persistence under challenging maintenance regimes. During TWCA trialing, the Low Maintenance Protocol is considered supplemental to the Protocol.
TWCA uses its Low Maintenance Protocol to conduct what we call Lawn Maintenance Trialing. Lawn Maintenance trials are the most punishing of all TWCA trials. Tey include a cap on fertility, a limit on herbicides and pesticides, and mandated use of a rotary mower.
Regardless of the trial type, TWCA relies on digital image analysis (DIA) to collect objective data across multiple locations. Te use of standardized lighting and cameras allows the TWCA Research Review Committee to make meaningful comparisons between cultivars across locations. TWCA’s move away from subjective rating to an objective trialing program allows for direct conversations about how TWCA qualified cultivars fit within a water budget. Tis methodology also allows the program to quantify the differences in cultivar drought tolerance.
TPI Turf News January/February 2018
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68
