2012 Annual Report for FNC12-854
Economic Comparison of Mechanical and Hand Pruning of Northern Cold Climate Grape Hybrids in Small Wisconsin Vineyards
Summary
WORK ACTIVITIES
Due to the early spring in 2012 we did not have a mechanical pre-pruner leased for spring pruning. These units are not made in the USA and are very rarely available used.
We did decide which rows would be hand pruned and which would be machine pruned. We found a farmer who was willing to purchase a barrel pre-pruner. This unit was purchased from a firm in Canada. We entered into a lease contract to use this machine in the spring of 2013 and 2014. Because our first machined vineyards were pruned in January of 2013 we will be running this trial in 2013 and 2014. We have completed our mechanical pruning and all of our hand pruning at both Danzinger Vineyards and Whispering Pines Vineyards. The grapes pruned in the study are: Marquette, LaCrosse, La Crescent, and Prairie Star.
All of these grapes have a plot of hand pruned and a plot of mechanical pruned vines. This mechanical pruning was done in January of 2013. The hand pruning was finished before bud break.
RESULTS
It takes a good sized tractor to run this machine. The biggest problem being the weight of the machine. The unit we are using was designed to front or side mount. We ended up mounting it on the 3 point because of the weight.
Because of our hilly terrain when it snows it is not possible to use this unit. We think the best time to use this unit will be in the late fall after dormancy and before snow. We are afraid that in the spring it will be too muddy to use this unit.
On moderate to steep slopes mechanical pruning is difficult if not impossible when wet or snow on the ground. Best time to mechanical trim is when ground is frozen and no snow cover.
Another issue is that when mechanical pruning, we are cutting the vines into small pieces and the way we removed them from the vineyard will not work. In the past we would use a modified landscape rake on the 3-point of the tractor and drag the long trimmer out of the vineyard and pile them up to burn. We hand raked any vines that were under the vines in the row to get them out.
After mechanical pruning we have decided to use a hydraulic driven broom mounted on the front of a tractor to sweep the vines into the space between the rows. We have purchased a 3-point shredder that we can use to grind the vines into small pieces and leaves in the vineyard. This requires some investment in equipment but requires less labor. Some people question if leaving these pieces in the vineyard will promote disease. Only time will show if we have disease issues from this practice.
WORK PLAN FOR 2013
• We have hired a college student who has taken grape production classes. He will be employed from May 10 until December. He will develop forms to collect the data on the quality and yield of the grapes. He will be in charge of collecting this data.
• Data will be collected from bud break until harvest is finished. We will use the mechanical pre-pruner late next fall.
• Data for this project will be collected in the fall of 2013 and fall 2014.
OUTREACH
• We have had an article in Grapevine which is a small Midwest grape publication.
• We also showed video of our unit working at the Wisconsin Grape Growers Association Spring Pruning Clinic. There was too much snow to demo the unit in the vineyard but we did have it setting out. This demo was on March 16, 2013. We had 33 people in attendance. This demo was held at Danzinger Vineyards.
• We also hauled the unit done to Westby, Wisconsin and did a demo at the Vernon Country Grape Growers Spring Meeting on March 23 at Whispering Pines Vineyard. We had 16 people in attendance.
• We will be giving a talk on machines in the vineyard at the Wisconsin Grape Growers Annual Meeting and at Minnesota Grape Growers (Cold Climate Grapes).
• We will take more video of machines in the vineyard this spring and summer including, Pre-Pruner, Row Brush, Vine Shredder, Air Blast Tower Sprayer, Vine Trimmer, Leaf Puller and Netting. We have access to all the above equipment. The only major hand labor will be final hand pruning and picking.