Managing the Temperature and Other Conditions Inside the High Tunnel
Resource 1.
Real-time Report of Current Conditions In- and Outside Eight High Tunnels in Wooster, OH and the Ventilation Status of the High Tunnels
Compare the current conditions in and near your high tunnels with conditions in and near eight high tunnels at the OSU-Wooster Campus in Wooster, OH. Use the comparison to help explain and optimize conditions in your high tunnel(s). In the process, pay close attention to the ventilation status of your and our high tunnels.
All the high tunnels referenced below are gothic-framed and single-layer and at Horticulture Unit 1 of The OSU’s Research Farm facility in Wooster, OH. They also contain two, 4 ft x 8 ft sliding doors on each end. HTs 101, 103, 203, 204, and 301 measure 21 ft x 48 ft, are oriented north-south, and lack endwall vents. HTs 501, 502, and 503 are approximately 1,000 ft from the other HTs and measure 30 ft x 80 ft, are oriented east-west, and have endwall vents with standard temperature-actuated wax cylinders. Additional information on the high tunnels and our setting their ventilation statuses is below.
Environmental conditions in- and outside these HTs and their ventilation statuses are reported in real-time below. External and internal environmental conditions are updated every fifteen minutes and ventilation statuses are current – refreshed within seconds whenever the position of an endwall door or sidewall curtain is changed. Different ventilation statuses are used at the same time to test and show the effects of each status on conditions inside the HTs. Ventilation statuses are set by learning, and with current crops and conditions and local weather forecast (see https://forecast.weather.gov/MapClick.php?CityName=Wooster&state=OH&site=CLE&lat=40.8185&lon=-81.9329&FcstType=graphical) in mind. HTs 101, 203, 301, and 503 are currently fallow, having been cropped to either a warm-season, mixed-species cover crop (101, 203, 301) or a mix of vegetables, herbs, and flowers (501) in Spring-Summer 2024. Also, HTs 103 and 204 currently contain butternut squash while HTs 502 and 503 contain carrot, okra, pepper, and sunflower. Crops in all high tunnels will be established/replaced in coming weeks. Also, HTs 501, 502, and 503 are exclusively drip-irrigated whereas all other HTs are currently irrigated using an overhead system. Overhead irrigation can affect temperature and RH levels in the HT directly while in use. Finally, as described at https://u.osu.edu/vegnetnews/2024/08/17/a-better-high-tunnel-poly-covering/, HT 103 is covered with an experimental, durable, high performance film whereas HT 204 (and all others) is covered with standard 6 mil poly. We are collaborating in the evaluation of the alternative film, including by recording the level of photosynthetically active radiation (PAR) in HTs 103 and 204. Measuring PAR, temperature, and relative humidity in both HTs but keeping their ventilation statuses identical at all times will allow us to describe effects their coverings may have on those variables. PAR data for HTs 103 and 204 are shown below (please consider data beginning 11:30 AM ET 9/12/24).
High Tunnel Environment Conditions High Tunnel Ventilation Status General Information
High Tunnel Ventilation Status
The ventilation status of a high tunnel is comprised of the relative “open-ness” of its endwall doors, sidewall curtains, and vents (if any). Each high tunnel can be in any one of hundreds of ventilation statuses at each moment, as determined by the manager or an automated system (see as summarized in an earlier VegNet News article for more information). For example, consider that individual endwalls and sidewall curtains can be 0%, 25%, 50%, 75%, or 100% open and it becomes clear that 625 statues (combinations) are possible (5x5x5x5). The ventilation status of a high tunnel influences the movement of air into, within, and out of it. The current ventilation status of each of the high tunnels referenced above is listed below.
General Information
Field 5 – Horticulture Unit 1
Field 15 – Horticulture Unit 1