Turfgrass Water Conservation Alliance (TWCA) created the Irrigation Calculator (based on this calculator from Pennington) to help end-users predict the runtimes of their irrigation systems. Simple.
TWCA collaborated with a network of public and private researchers including Oregon State University, University of Washington, University of Arkansas, and NexGen Plant Science Center, on a series of multi-year inquiries to answer some basic questions about site specific conditions.
The Irrigation Calculator is simple. Click the greenness of your grass (fun fact: during development we called this the "lush level"). Know the irrigation rate and weekly frequency. Remember where you live. It's true, there are some curveballs in there; not everyone knows if they have TWCA Qualified turfgrasses, but generally, pretty spoon and June.
The calculator itself is an example of interdisciplinary cooperation on a public/private partnership resulting in an immediately useful tool.
Turfgrass Water Conservation Alliance (TWCA) relies on our cooperators to conduct trialing. We recognize that our work is only a small part of what you do on your farm and that tracking the details of the study is not something you want to worry about. We also know you want to talk about all the cool and interesting work you spend your time on and we certainly hope TWCA is on the list of things you want to discuss.
To make it easier to express the scope and scale of the TWCA trialing we have created this list of talking points about the trial(s) TWCA is currently running.
Cultivar Plant Factor (CPF) proves an effective tool in defining and quantifying the term “drought tolerance” with relation to turfgrass evaluation. CPF methodology encourages performance-based selection relative to a known standard over broad geographic range. CPF also moderates the impacts of over and under performance years. Correctly applied CPF methodology offers a powerful tool to water providers seeking to drive sustainable outdoor water conservation solutions.
Preparations for a successful trialing year are well underway at Turfgrass Water Conservation Alliance (TWCA). With the completion of the first TWCA Cooperators call in and the final check off for TWCA cameras both finalized in February the pressure is on to get equipment shipped. As the first program to require objective data TWCA is the industry leader in standardizing research equipment and practices. TWCA calibrates and inspects a fleet of standardized equipment to ensure accurate trialing results meaningfully compared across locations. TWCA Standardization efforts also include the cooperator calls happening three times per year to discuss management issues and update the research team on progress and challenges. Other supplements include standard TWCA Talking points specifically for cooperator trials, FAQ handouts addressing specific cooperator questions from prior trials, and Growing Great Grass, the TWCA cooperator manual. TWCA also issues a set of standard research lights; this half dozen lights ensure cooperators have access to 1.5 full arrays of fresh bulbs with the same anticipated lighting profile. The point of all this standardization is simply to remove confounding factors from any trialing results, giving the clearest view of drought tolerance in turf.
Predictability and reliability are essential for long term reliability. In an industry where development is, sometimes, years in realization, TWCA is providing a schedule for trialing. Released today, the trialing schedule is an important tool for Seed Producers and trialing cooperators alike.
The site improvements include features requested by TWCA members. Improvements like, simplifying Qualified Cultivars page and making it easier to find specific members. Enhancing the simple interface for users looking for drought tolerant turfgrasses to reduce the water demand of their landscape by 30%, is a consistent, current, and easy to use locator on the site tgwca.org. Clear icons make it easier than ever for end users to find the product they need, while putting the same map on multiple pages means it is never more than a click away!
An especially informational feature, the new TWCA Timeline puts a long scroll format timeline front and center. Not only does this highlight the incredible contribution of TWCA to sustainable landscapes but it also shows the dedication of the turf breeders and TWCA members to the consistent improvement of turfgrass.
Finally, rounding out the public nip/tuck, is cleaning up the menu bars and pages. By consolidating the Growing Green and Irrigation Calculator under the Home page the menu eliminates clutter and makes it easier for users to navigate to what they need.
Behind the scenes, for members, in the Members Only portion of the website, TWCA has added an area for scheduling webinars and distance learning opportunities, a downloadable version of the MWERLO calculator, and some new member benefits.
All together this update helps improve the usability of the site.
SLC Public Utilities Water Conservationist, Stephanie Duer is reporting a 50% reduction in water use at the Concord Lifting Station in the months following the landscape conversion for SLC Turf Trade. The location was selected for conversion as a demonstration canvas for landscape practices suggested by the Center for Water Efficiency (CWEL). This conversion incorporates a number of different landscaping practices to maximize water efficiency. Common landscape tactics for increasing water efficiency include hydrozoning, or grouping plants according to their water need, turf area reduction, and optimizing irrigation design and hardwater for water efficiency.
Turfgrass Water Conservation Alliance (TWCA) created the Data Evaluation and Statistical Analyst (DESA) position. Filling this position for the inaugural role is Tyler Carr, graduate student at University of Tennessee, Knoxville.
“This position is the confluence of TWCA’s efforts to provide, sound scientific trialing to the turf community while elevating the next generation of scientists,” says Jack Karlin, Program Administrator of TWCA.
Despite this being the inaugural position, Carr, is no stranger to TWCA. His prior experience with TWCA came at University of Arkansas with Dr. Doug Karcher, Chair of The Ohio State University College of Food, Agricultural, and Environmental Sciences (CFAES) Department of Horticulture and Crop Science (formerly of University of Arkansas) conducting lysimeter testing on turfgrasses determining the impact of soil texture on volumetric water demand. This work served as a keystone in developing TWCA’s innovative Water Calculator (turfgrasswaterconservationalliance.org).
Tyler’s nomination to this position came from Dr. Karcher. “I knew I wanted to pass this responsibility to someone who was qualified, experienced, and capable,” says Karcher. “Tyler is exactly the right guy for this.”
As the fire season rages through the West (and around the world) it is time to pay more attention to the ecological benefits of our managed environment and the role turfgrass can play in these systems. Check out this great article in the Oregonian!
Fire smart landscaping doesn’t have to look like the desert
A major factor driving the growth of solar power in the US has been the economics of large, utility-scale solar projects. The scale of plants ensures that their developers can buy components in bulk, use larger, more robust hardware, and install everything efficiently. That's in major contrast to most distributed installations, like rooftop solar.
But these installations do come with downsides. They often occur on undeveloped land, which can offset some of their positive contributions to climate change, especially if the land that has to be cleared was sequestering carbon. Ideally, it would be better to find a way to mix the best features of both—use previously developed sites, but on a scale that puts them on par with dedicated installations.
One of the solutions that has been floated (pun intended) is to put the panels on reservoirs. Reservoirs are large and already developed, and there's a side benefit of floating the panels onto the water: it cuts down on evaporation, potentially enhancing the value of the reservoir. Now, researchers have examined an alternative: covering all of California's open-air aqueducts, which supply one of the most productive agricultural regions on the planet, with photovoltaics.
Built on a body of research coming out of NexGen Turf Research and University of Arkansas the TWCA Irrigation Calculator is designed to educate homeowners on appropriate run times for turf irrigation. With a broad coalition of researchers in public and private research institutions, TWCA provides a useful education tool to reach end-users and educate consumers about the different choices they can make when managing their outdoor water use.
The TWCA Irrigation Calculator estimates irrigation runtimes across the contiguous United States. These estimates account for many of the physical characteristics of a site including ET, soil type, turf water requirements, and even desired green cover affecting water requirements. This project is the culmination of multi-year collaborations with University of Arkansas, Oregon State University, and University of Washington.
The first question that needed answering for TWCA was, “What role does soil type play in volumetric water demand?” To answer this, TWCA turned to then graduate student, Tyler Carr at University of Arkansas and his Professor, long-time TWCA Collaborator, Dr. Doug Karcher.
The type of soil a turf is grown on can drastically affect irrigation practices. Soils high in sand content have a lower water holding capacity than silt loam soils, therefore turf grown on sand must be irrigated more frequently to achieve desired turf quality for a lawn. Prior to this project with the TWCA, it was unknown whether these soil types varied in the actual volume of water required over a given period in the absence of rainfall.
The results from this project indicate that, under prolonged drought stress, soil type has minimal effect on overall water consumption. The implication for homeowners is that turf can be irrigated three times weekly without using any more water than if all the irrigation was applied during a single weekly application. This is especially important if the turf is grown on a sandy soil, as weekly irrigation can negatively affect turf quality.
After determining the impacts of soil type on water requirements TWCA moved to incorporating soil type, ET data, and precipitation from historical averages into a model. All data was aggregated from free publicly available resources.
Dr. Zhao at Oregon State University (now at University of Washington, Seattle) led the efforts to create the Irrigation Calculator from the data available. Bo and his team scrubbed the data and created the tool as it currently sits.
The development team was forced to make some assumptions in the interest of efficacy. The most noticeable is the warm season turf range being drastically limited compared to that of the cool season range. Given the difficulties of the transition zone and the ever so slight edge of survival afforded to cool season turf TWCA chose to maximize the range of cool season turf while maintaining a limited range for warm season options.
There are many warm season turf cultivars that have excellent cold tolerance and thrive well north of the TWCA’s default assumption and we encourage everyone to find those cultivars best suited to their growing conditions.
As a team, we also chose to use the native surface soil layer as the default soil type. In some areas where the data was sparse, we extrapolated soil types from the surrounding areas.
Using the Irrigation Calculator is a snap. End users simply select the green level they are looking for, the precipitation rate of their irrigation system and verify the watering month. Finally, enter the correct zip code or city name to get the desired irrigation run time in minutes.
Users should note that the TWCA Irrigation Calculator does not accurately evaluate irrigation precipitation rates greater than one inch/hr. This conscious choice only affords end users the option of using more water efficient gear drive or rotary nozzles.
Even though the TWCA Irrigation Calculator is a great reference tool it is not perfect. The Calculator does not account for root zone depth, water lost to management or slope on site; these are all special considerations that will affect the cycling of the irrigation system.
TWCA sees a future for this tool expanding the function to include the entirety of the United States and Canada. As the tool develops, we are also looking to create greater responsiveness to rain events, increase the range of irrigation precipitation rates to accommodate professional users, and potentially include links to outdoor water conservation programs for TWCA Government members.
Jack Karlin is the Program Administrator for TWCA. His interest is in using policy and the built environment to create livable and sustainable communities.