Spur Pruning May Be a Viable Option for Oregon Pinot noir Producers Despite Industry Fears of Lower Productivity

Goals: Winegrape production is more costly in Oregon than in other US growing regions, and industry faces rising production costs and labor concerns. Growers are considering ways to reduce labor and introduce mechanization. Spur pruning requires less labor and is more readily mechanized than cane pruning; however, the majority of Oregon growers use cane pruning. We conducted industry surveys and interviews to understand why cane pruning is preferred and determine potential barriers to adopting spur pruning. We conducted a vineyard case study to quantify fruitfulness and yield of cane- and spur-pruned vines to determine the potential for spur pruning in Pinot noir.

Key Findings:

• The majority of survey respondents (76%) primarily used cane pruning on cool climate cultivars because they believe that spur pruning reduces yields and fruit quality and increases fungal and mite pests. A total of 35% believed that spur pruning reduces yield due to vines having unfruitful basal buds.

• Interviews of Pinot noir growers who use both spur and cane pruning revealed that spur pruning could achieve desired yields, while reducing production costs and labor dependency. Their observations did not support survey respondent concerns about severely reduced yields, fruit quality, and increased mites or diseases.

• The Pinot noir vineyard case study revealed that cane and spur pruning led to similar yields, cluster size, and fruit ripeness. Data from spur-pruned Pinot noir vines showed that shoots arising from basal, first, and second buds were fruitful.

Impact and Significance: Industry perception and lack of experience with spur pruning is preventing adoption. Expectation of low yields is based on industry hearsay, not direct experience. Concerns that spur pruning lowers quality may be derived from mechanization research from regions that focus on quantity, not quality. However, grower interviews and field data show that Pinot noir is fruitful at basal nodes and can be spur pruned without limiting yield or quality based on Oregon standards. Converting to spur pruning reduced pruning cost, and research/demonstration projects are needed to help small, quality-focused industries make necessary adaptations to their production systems.