Waiting on a mule deer crossing…
Equipment: polyvinyl chloride (PVC) pipe, Lumite mesh cloth, zippered openings, metal flashing
Manipulate herbivore abundance
Assigned each cage to either grasshopper removal or addition. Captured grasshoppers via the remove and in the meadow adjacent to the garden via sweep netting and released them into the addition cages. Added grasshoppers once per week in 2021 and 2022 and three times per week in 2023, which elevated grasshopper density above ambient levels. Natural grasshopper density was lower in 2022 than in other years.
Quantities: Once per week in 2021 and 2022, three times per week in 2023, elevated grasshopper density above ambient levelsDuration: Weekly to tri-weekly additions during growing seasons 2021-2023Conditions: Field conditions during growing season
Equipment: sweep nets
Manipulate water availability
Subdivided cages into four blocks, with two blocks assigned to each water treatment: supplemental or restricted. For supplemental water blocks, supplied 1.5 L of water twice a week with watering early in season (June-mid-July) when rain was infrequent. Once monsoons began in mid- to late July, ceased irrigations at supplemental water. For restricted water blocks, deployed rain-out shelters constructed of polycarbonate sheets angled so rain and runoff flowed to the edge of cage, away from experimental plants immediately before forecasted rain.
Quantities: Four blocks per cage, two blocks per water treatment, 1.5 L water twice per weekDuration: Watering June-mid-July when rain infrequent, rain-out shelters deployed before forecasted rainConditions: Early season (June-mid-July) when rain infrequent, before monsoons in mid- to late July
Equipment: polycarbonate sheets, rain-out shelters
Monitor soil moisture
Monitored soil moisture in all 24 blocks twice a week using a Hydrosense. Volumetric water content was significantly greater under supplemental than restricted watering across all three years.
Quantities: 24 blocks monitored, twice weekly measurementsDuration: Twice weekly throughout growing seasons 2021-2023Conditions: Field conditions
Equipment: Hydrosense (Campbell Scientific, Logan, UT, USA)