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There are ≈40 million acres of turfgrass lawns throughout the United States, most of which are managed under chemical-intensive pest and fertilizer programs. “Organic lawn care” is being adopted more widely; however, unlike the formally defined policies and regulations that govern organic agriculture, the label organic lawn management has not been formally defined and is used to describe a variety of practices. Neighborhoods, cities, states, and provinces across North America are adopting policies regulating the use of pesticides and fertilizers in the landscape. In addition, a small but growing number of public institutions and individual consumers are successfully adopting alternative lawn care methods, including organic lawn care. Although perceived as environmentally friendly, the effects of organic management on insect diversity and pest management remain understudied. Organic lawn management may lead to increased lawn plant diversity, which in agroecosystems has enhanced ecological services provided by beneficial insect species. Effects of vegetative diversity on lawn pest management are less clear. Vegetative complexity and increased plant diversity in urban landscapes may enhance insect predator efficacy. The diversity of predatory insects varies between turfgrass varieties in response to prey populations. Mortality of insectivorous and granivorous ground beetles (Carabidae) while not directly impacted by pest management programs in turfgrass may be indirectly impacted by a reduction in the prevalence of plant species that provide alternative food resources. Previous studies have focused on herbivorous insects as well as predatory and parasitic insects that feed on them. Future studies should assess how lawn plant diversity resulting from organic management practices might impact insect communities in turfgrass.

Pulse irrigation, the practice of applying water in small doses over time, is known to reduce deep percolation and runoff and, relative to irrigating in single continuous applications, can increase plant growth and production by supplying water and nutrients at an optimal rate. The objective of the present study was to determine whether pulse irrigation was beneficial in red raspberry (Rubus idaeus L. ‘Wakefield’). Treatments included continuous or pulse drip irrigation and were evaluated for three growing seasons (2018–20) in a commercial field with silt loam soil. Continuous irrigation was applied up to 4 hours/day, whereas pulse irrigation was programmed to run for 30 minutes every 2 hours, up to eight times/day, using the same amount of water as the continuous treatment. Pulsing improved soil water availability relative to continuous irrigation and, by the second and third year, increased fruit production by 1210 to 1230 kg·ha⁻¹, which, based on recent market prices, was equivalent to $2420 to $2460/ha per year. Much of this yield increase occurred during the latter 3 to 4 weeks of the harvest season and was primarily due to larger fruit size during the second year and more berries per plant during the third year. In 1 or both years, pulse irrigation also produced more canopy cover, larger cane diameters, and higher concentrations of Mg and S in the leaves than continuous irrigation, but it reduced K and B in the soil and had variable effects on sugar-to-acid ratio in the berries. On the basis of these results, pulsing appears to be an effective means of irrigating raspberry plants in sandy or silty loam soils, but more research is needed to determine whether it is useful technique in heavier soil types.

A 2-year trial was established in Oct. 2016 in western Oregon to evaluate the effects of various in-row mulch treatments on the establishment of northern highbush blueberry (Vaccinium corymbosum L. ‘Duke’). The treatments included douglas fir [Pseudotsuga menziesii (Mirb.) Franco] sawdust, black weed mat (woven polypropylene groundcover), green weed mat, and sawdust covered with black or green weed mat. Soil temperature was unaffected by the color of the weed mat, but it was often higher during the day in beds with weed mat mulch than in those with sawdust alone or sawdust covered with weed mat. Black or green weed mat also resulted in higher canopy temperatures, particularly when sawdust was underneath the weed mat. Plant growth was mainly unaffected by the color of the weed mat, and the maximum depth of the root system was similar among the mulch treatments. However, plants grown with sawdust mulch, with or without weed mat, had a greater canopy width and volume in year 2, a wider root system in both years, and more dry weight (DW) in the crown in year 1 and in the whips in year 2 than those with weed mat alone. Furthermore, plants with weed mat over sawdust were taller in year 1 and had greater canopy cover and more DW in new wood in year 2 than those with sawdust alone, and they had a larger canopy, more root development, and greater DW in the crown, new and old wood, fruit, and pruning wood in one or both years than those with weed mat alone. Over the course of the 2 years of the study, the net gain in total plant DW was lowest when the plants were grown with black weed mat and highest when they were grown with black weed mat over sawdust. Although it was more expensive initially, the use of weed mat over sawdust resulted in more plant growth than weed mat alone due to the insulating properties of the sawdust, and it was more effective for weed control than using sawdust alone.

Hot and sunny weather can cause a considerable amount of fruit damage in northern highbush blueberry (Vaccinium corymbosum L.) and result in millions of dollars of crop loss each year. To combat this issue, many growers use over-canopy sprinkler or microsprinkler systems to cool the fruit, but questions remain on the amount of time and frequency these systems should be run and whether they have any effect on fruit quality. Two series of studies were conducted to evaluate the efficacy of using sprinklers or microsprinklers for reducing blueberry fruit temperature and improving fruit quality in western Oregon. With sprinklers, treatments were applied in 2014 and 2015 to ‘Elliott’ blueberry and included irrigation (night) and cooling (day) with sprinklers, sprinkler irrigation (at night only) with no cooling, and drip irrigation with no cooling. The sprinklers were run for cooling for 15 minutes every hour whenever air temperature was ≥32 or 35 °C. Berry temperature declined rapidly within the first 15 minutes of cooling and never exceeded ambient air temperature during the cooling cycles. While the percentage of fruit with heat damage was low even without cooling (<2%), cooling reduced damage to nearly 0% in 1 of 2 years and increased berry weight relative to no cooling in both years when it was run at ≥32 °C. Cooling also reduced the concentration of soluble solids (sugars) in the berries in 2014 but had no effect on yield, fruit firmness, titratable acidity, harvest date, or the total content of phenolics or anthocyanins in the berries in either year. With microsprinklers, cooling was tested at a commercial farm and at an experimental site. At the farm, 1.3-ha blocks of ‘Aurora’ blueberry were irrigated by drip and either had no cooling or were cooled using microsprinklers run continuously or pulsed in 1-hour or 20-minute cycles during three extreme heat events (≥35 °C) in 2015. Continuous cooling was the most effective treatment for reducing berry temperature, but it resulted in wetter conditions, which might impede fruit harvest afterward and increase the presence of slugs, insect pests, and fungal diseases. Pulsed cooling, especially with short cycles, effectively maintained fruit temperatures near that of ambient air and reduced water use by 50%. At the experimental site, cooling with microsprinklers, which in this case were pulsed in 20-min cycles when air temperature was ≥ 32 °C, reduced heat damage in ‘Aurora’ and ‘Elliott’ in 2016. Cooling at this site also increased berry weight by an average of 10% in both cultivars and increased fruit firmness by 32% during the first of three harvests in ‘Aurora’; however, it reduced the concentration of soluble solids in the berries in both cultivars. In general, cooling with microsprinklers used considerably less water than cooling with sprinklers, but it appeared to be equally effective at reducing berry temperature.

Northern highbush blueberry (Vaccinium corymbosum L.) often requires frequent irrigation for commercial production, but irrigation is becoming increasingly challenging for many growers because of warmer and drier weather conditions, increased water regulations, and other water-use limitations. The purpose of this study was to develop improved methods of irrigation to prepare the industry more effectively against future water uncertainties. Treatments were applied for 2 years (2021 and 2022) and included a combination of weather-based or fixed irrigation schedules using continuous or pulse irrigation in a commercial field of ‘Draper’ blueberry in eastern Washington, USA. The soil at the site was a silt loam, and irrigation was applied using two laterals of drip tubing per row. Plants on a fixed schedule were irrigated for 12 to 13 hours per application (set by the grower), whereas those on a weather-based schedule were irrigated according to daily estimates of crop evapotranspiration (downloaded from an automated weather station). In both cases, irrigation was applied every 2 to 4 days as a single, continuous application or in 30- to 50-minute pulses every 2 hours (up to nine times per day) with the same amount of water as the continuous treatment. During the first year of the study, weather-based scheduling maintained greater stem water potentials in the plants and, on average, increased yield by 3.4 t⋅ha^–1, berry weight by 0.14 g/berry, berry diameter by 0.4 mm, and fruit bud set by 4.3% when compared with fixed scheduling. Likewise, pulse irrigation maintained greater stem water potentials and, on average, increased berry weight and diameter by 0.10 g and 0.4 mm, respectively, fruit bud set by 3.3%, and canopy cover by 2.4% relative to continuous irrigation. Yield and canopy cover were unaffected by any treatment in the second year, which was likely a result of uncharacteristically cool, wet weather in the spring. However, weather-based scheduling continued to maintain greater stem water potentials and, when combined with pulse irrigation, increased berry weight and diameter by 3.7 g and 1.0 mm, respectively, relative to continuous irrigation on a fixed schedule. Pulse drip irrigation also increased fruit bud set by 5.1% during the second year. These results demonstrate the potential benefits of using weather-based scheduling and pulse drip in northern highbush blueberry, especially when the plants are grown on light-textured soils in hot, dry climates.