Week 19 (Oct. 28th - Nov. 1st)

Every year 90% of  the new growth needs to be pruned off the vine in order to keep its health in check. This project generally happens in the heart of winter, Jan and Feb, but j-vines like this (ones that aren't cold-tolerant) need to be pruned soon after the first frost, pinned into the ground, and then buried with straw before a true cold sets in. We have therefore begun pruning all of our j-vines and I am patiently learning the art. During pruning one needs to take into account factors like trunk injury, bud positioning, a renewal spur positioning for future years of pruning when determining which shoots/trunks to remove. 

This is the same vine after being pruned. We utilized cane-pruning on this vine, meaning shoots from this year (canes) will be laid down and attached to the fruiting wire in the spring. The alternative method to this is retaining cordons (or extensions of the original trunk) and cutting this year's shoots down to two node "spurs". In either case, this year's growth is saved (either as canes or spurs) because only this wood will produce fruiting shoots next year. The canes/spurs must have substantial wood ripening (periderm/bark formation) in order for the buds to produce viable shoots and clusters. The "primordia" (next years shoots before they begin telescope from the bud) form throughout the entire previous season, therefore it is important that the buds are well exposed to light before they go into dormancy. You can see here that we retained three trunks and five canes. One of these canes (the one that experiences the most winter damage) will be pruned off in the spring, while the other four canes will be attached to the wire, two in each direction. 

This is evidence of winter injury. The pith in the center is dead, along with a wedge of wood. You can tell that this injury happened last winter, as there is a new layer of wood to the exterior of the wedge (this year's growth). I bet that there was a nick in the bark along this section of the trunk which exposed the wood to cold winter air. The circular speckles are also winter injury, representing dead companion cells around what used to be xylem. These cells must have frozen as well, and may even represent years of slight winter injury. 

We need to analyze when malolactic fermentation is complete in all our reds and various whites. MLF is not actually a fermentation, but rather a bacterial inoculation that converts malic acid to lactic acid. This can be beneficial as malic acid is harsh on the palate, where lactic is soft. Also, this process can contribute butterscotch aromas to the wine, which at times is beneficial. Ever notice these buttery notes in your favorite Chardonnay? In order to determine if MF is complete we use a spectrophotomer (light spectrum meter) to measure light absorbency due to concentrations of glucose and fructose, from which malic acid concentrations can be extrapolated. This cuvette contains 100 micro liters of wine and two mL of a buffer solution. We measure how much light is absorbed by this, then add an enzyme and measure it again. The change in asorbance allows us to determine if MLF is complete. Those years of chemistry are finally paying off!

Week 19 (Oct. 21 - 25th)

The ground is finally damp enough to permit us to remove the vines that have been rejected from the breeding program or have died throughout the season. Since decaying roots in the ground can hinder the development of young vines, we use this hydraulic lift (called a Dingo) in order to pull the rest of the plant out of the ground. Grape wood makes great smoking wood, so we are lopping off and saving all the trunks! 

This plant appears to have a healthy root system, so it's fruiting potential must have lead to it's demise. Notice how there are many fine-haired "feeder roots" near the surface and larger "sinker roots" deeper in the soil profile. The feeder root's high surface area allows them to quickly absorb nutrients (with the help of mycorrhizal fungi) and water, while the sinker roots are utilized for carbohydrate winter storage and seeking out water in times of drought. These roots also help stabilize the plant. It's hard to tell in this picture, but you can also see how the roots emerge at each subterranean node and therefore form in tiers. 

The bumps near my thumb are evidence of Crown Gall. This bacterial infection is problematic after hard winters, which cause the sensitive trunks to crack and become exposed to the pathogens. Areas affected by crown gall will eventually die. This can significantly restricts the xylem flow from the roots and eventually will kill the plant. 

I capped off the week Friday by mowing all the aisles one final time for the season. I passed down each row four times in order to ensure that the grass was short enough to discourage mice from making winter homes in the vineyard. If food sources get scarce, mice will resort to eating bark from the vines, effectively girdling the plant. As you can see, we experienced our first hard frost this week as well. This means that all photosynthesis productions is done for the season, all fruit and wood ripening has occurred, and carbohydrate storage has finished. The vines are not going into dormancy, preparing for the long, cold winter ahead. 

Week 18 (Oct. 14 - 18th)

I went on a road trip Saturday to Melrose, MN in order to help John finish harvesting his vineyard.We lugged away 5,000 lbs during the day-long adventure, all of which is being made into wine at the Parley Lake Winery. To conclude and toast the harvest season John "saber-opened" a bottle of champagne, a old tradition of Germany. He used a knife (but traditionally it would have been a sword) to perfectly crack open the bottle top. 

We continue to harvest grapes a the HRC as they continue to ripen and become more palatable. However, grape varieties with thin skins are starting to break down and attract more Asian beetles and wasps! This makes harvesting a slower and more painful process. The chemical in the beetle's hemolymph (orange goo) is supposed to make a wine taste like burnt peanut butter, which apparently is a bad thing. 

We received a few coolers of grapes this week from growers around MN in order to analyze how the chemistry varies between locations (or more specifically soil conditions and cultural practices). I crushed the clusters by hand, collected two viles of the juice for each, and then recorded pH, TA and degrees brix.

As we scour the vineyards for the latest varieties to pick, we are also making sure to find all the breeding bags. These wax-paper bags contain clusters of the grapes which we cross-pollinated by hand back in June. 

Though this project has been on the back-burner for the whole summer, it is the foundation of our breeding program and therefore one of the most important tasks that we will perform each season. We carefully extract the seeds from the pulp, rinse and scarify the seed coats, dry the seeds and rub off leftover sugars, and then count the exact number per cross. Though the seeds all look identical, each has unique and carefully selected genetics that need to be properly recorded. If this part of the process were to be done improperly, the breeding program wouldn't progress for the next two years. The seeds were all counted three times, totaling to a little over 6,000!