- Agronomic: hops
- Crop Production: conservation tillage
- Education and Training: extension, farmer to farmer, on-farm/ranch research, workshop
- Farm Business Management: agricultural finance
- Production Systems: organic agriculture, permaculture
- Soil Management: organic matter, soil analysis, soil quality/health
- Sustainable Communities: new business opportunities
1. Determine the growth habits, yields, quality, and market potential of the hop cultivars "Summit" and "Teamaker" on a low-trellis system under Great Lakes growing conditions.
2. Assess the effects of understory nitrogen fixing cover crops on soil quality, soil nitrogen levels, hop leaf nitrogen, and weed control.
3. Conduct a cost/benefit analysis of low-trellis vs. hi-trellis organic hop production systems.
Michigan has experienced considerable growth in the number of microbreweries in recent years and beer production has followed suit. In 2007 Michigan produced 170,000 barrels of beer; by 2009 the number had increased to 221,000 barrels (Rex Halfpenny, MI Beer Guide 2010). In 2008, a short supply of hops worldwide led to drastic price increases and a shortage of hops for smaller-scale craft brewers. Results of a comprehensive survey of all Michigan brewers suggested that: 75% were slightly-definately concerned about the market security of hops; 100% were interested in sourcing local hops; and over 50% suggested they would pay a premium for locally grown organic hops (Sirrine et al. 2010). Yet there is currently unmet demand for local organic hops. The October 2010 decision by the National Organic Standards Board to remove hops from the exemption list by January 2013 will increase organic hop demand. However, organic hop systems struggle with fertility and weed management and standard hi-trellis system establishment costs are more than $10,000/acre in Michigan. To meet the expected demand for organic hops, growers will need to improve fertility and weed management, and reduce establishment and labor costs.
Like most organic systems, weed and fertility management are the major impediments to economically viable yields. In conventional hops, weeds are managed by tillage and herbicides. The effects of repeated tillage on soil structure, erosion, and nutrient retention are well documented in the literature. Weeds in organic Michigan hopyards have been controlled by tillage and significant quantities of straw mulch. While effective, these practices are both labor intensive and expensive.
Because of their vigorous growth habits (up to 8 in./day), mature hops require at least 100 lbs. of actual N/acre annually. The vast majority of nitrogen is taken up from mid-June until the end of July. Without the luxury of applying inorganic nitrogen, organic hop systems must have hi-levels of available nitrogen in the soil to ensure sufficient yields. While application of fish emulsion and compost has served as the standard fertility and soil building regime in Michigan organic hopyards, hop alpha and beta quality tests suggest that more nitrogen may be needed.
Because organic systems cannot use treated poles, MHA members have been using 24 ft. black locust and white cedar poles. In addition to the expense ($40+/pole), poles of this size are relatively difficult to source. Additionally, placing poles of this length in the ground, and installing trellis wire and coir strings is labor intensive and costly. For example, MHA members have spent hundreds of dollars renting Skytracks and bucket trucks for hopyard installation.
Proposed Sustainable Agriculture Solution
One promising solution is the low-trellis organic hop system. According to the USDA ARS (2008) low-trellis systems can reduce labor costs by 30% and, by our calculations, establishment costs by over 50%. However, because most traditionally grown cultivars have been bred for the hi-trellis system, selecting the right cultivar(s) is paramount for the low-trellis system to be successful. On a summer 2010 Yakima Valley tour, MHA members were able to discuss this issue at length with growers including Michael Roy, the largest organic hop producer and breeder in the U.S., and Washington State University scientists. Because of its growth habits and success in Washington State production, the cultivar Summit was the clear choice among the group for a low-trellis system trial in Michigan. Moreover, Summit is a cultivar in high demand from Michigan brewers (Right Brain Brewery, Shorts Brewery, New Holland Brewery, and Founders). The second cultivar we propose to plant is Teamaker. Developed in 2006 by the USDA ARS, it has particular medicinal qualities coveted by herbalists and tea-makers. It has low alpha-acid but high beta acid content, the latter of which is responsible for medicinal and anti-microbial properties. Organic production of Teamaker will serve to diversify the market for organic hops beyond the traditional brewer realm. Our proposal represents the first time these cultivars will be planted in the region.
Research site and protocol
On-farm manipulations will be carried out near Omena, MI on the Leelanau Peninsula, N45°04'6.24", W85°35'49.92". Average annual precipitation in the region is 30 in., with cold, snowy winters and warm, humid summers. The site is part of a functioning 4 ac. hi-trellis hopyard. The soils are Emmet-Omena sandy loams (2-6% slope), deep, well to moderately-well drained, with low to moderate available water holding capacity and organic matter content.
We will construct a 1.5 acre research plot of low-trellis Summit (5 rows) and Teamaker (3 rows) hops. Using a tractor mounted auger we will plant 14 ft. black locust poles, 4 ft. deep in eight rows of twenty-seven poles each. Poles will be placed by hand at 30 ft. intervals in a north-south direction for an overall row length of 810 ft. With spacing and planting density similar to a hi-density apple orchard, poles will measure lO ft. above ground and rows will be 11 ft. apart, thereby adhering to the 90% height to row-width ratio recommended in hi-density apple systems (Schwallier, 20lO). Hop rhizomes (2/hill) and plants (l/hill) will be planted in spring 2011 with a hill every 2.5 ft. (260 hills/row and 1560 total hills).
Trellis wires will be installed and end anchors augured to secure the trellis system. Drip irrigation will be installed (emitters every 2.5 ft). In year one, rhizomes will be irrigated at 1 g/hr for 3 hours, twice/week during the summer depending upon climate and moisture requirements (8 gallons/plant/week total). From year two forward, plants will be watered at 16 gallons/plant/week. Coir strings will be hung to guide hop bines and hops will be thinned to four bines/hill to encourage growth. To proactively control weeds, leguminous cover crops (red mammoth and dutch white clover) will be broadcast seeded in spring 2011 across the entire hopyard floor.