Week 17 (Oct. 7 - 11th)

This is a chimeric Frontenac cluster that John found in his personal vineyard. Growers need to watch out for these mutants during harvest because if this happened to be picked along with a batch of Frontenac blanc, the wine would have become a rosé just from these few berries.

This berry was 1/4 noir and 3/4 blanc! Cool, eh?

We get to crush and de-stem small batches by hand. We need to carefully remove as many (hopefully all) asian beetles as possible, as the smell of one crushed beetle can be detected throughout an entire batch of wine. This is a big problem in this day and age for commercial wineries too! Also, notice how the Marquette, and a few other reds, have been pressed and are now in carboys. These will continue to bubble until all sugar has been converted to ethanol and CO2 via the yeast.

A few whites being re-racked before fermented. We add an enzyme after pressing to drop out various proteins, which ends up leaving a sludge on the bottom of the carboy via gravity filtration. We rack the juice off of this before fermentation, then off the yeast after fermentation and maybe once more afterwards. During these stages the amount of air in the carboy above the juice isn't important, but in later stages of re-racking it is important to reduce the "head-space" to as little as possible. 

This machine may look fancy, and I guess it is since it cost more than $5,000, but it is actually pretty simple. It is an automated titrator, so all we need to do is insert the probe and calibrate it to two standards, add 5 mL juice and 45 mL DI H20 to each cup, and then press start. It adds NaOH incrementally, while mixing the solution with a propeller, until it balances the solution. Based off of how much NaOh is used it calculates and prints out a reading of every TA (titratable  (or total) acidity). A normal TA is anywhere 6 - 8 g/L, however our research grapes tend to come in around 10 - 12 (and therefore have a nice acid bite to them!).

Week 16 (Sept. 31 - Oct. 4th)

The yellow jackets have discovered that some grape skins are thinner than others and are therefore easy enough to chew into. This now makes it difficult to harvest, as we have to be careful where we grab the clusters. We have to pick out broken berries with our pickers, since these smell bad (have a high volatile acidity) and will make the wine taste bad. The broken berries are now also attracting flies and asian lady beetles! Yay!

An afternoon project with dad! I was fortunate enough to bring home substantial scrap pieces of trellis in order to build a trellis for my very own, lavish front-yard vineyard. After a few hours of digging and pounding, the trellis is complete and ready to support my six vines!

Jenny came back this week! She had been at home with the baby up until this point, but now the Thull Team is back in action (with their own language and everything!).

While the reds are fermenting, CO2 bubbles cause the skins to rise to the top (above the juice) and form a cap. In order to allow the wine to fully extract the color and flavor we need to "punch down" the cap twice a day. I have had to punch down the various Marquette batches this week. We tested out three different yeast strains, each of which will contribute its own flavors and aromas to the wine. The variation from yeast strain to strain is due to the different types of enzymes that yeast produce. The enzymes are important because they deglucosylate (remove a glucose) flavanols, making their aromas detectable.  

We stepped away from the vineyards and into the pumpkin/squash patches on Tuesday, the 1st, in order to harvest this year's crop. After many hours, and many sore backs, we harvested all 180 varieties totaling to roughly 10,000 lbs. Most of this will go on display in the Landscape Arboretum and sold at "The Apple House," which is a store connected to the research center. This had been Jenny and John's project all year. The effort definitely payed off!

Nick, the winemaker, and I chopped and pressed a few bushels of SweeTango apples on Friday. We ended up having more juice than we needed to run an apple wine test trial, so I was able to bring home a few gallons for myself. One of the many perks of working at the HRC! 

Week 15 (Sept. 23rd - 27th)

This is a clear example of a "bull cane." This shoot is characterized by excessive vegetative growth, which can be caused by various reasons. If soil nitrate levels are too high (or alternatively looking at it, if soil organic matter above 5%) vine shoots can be dominated by bull canes. However, this isn't the case for this vine since we don't fertilize and our organic matter is around three percent. You can see that the right cordon is dead (right above the cane), so therefore all nutrient and water supply from this half of the vine (maybe even a whole second trunk) is fueling the growth of this individual shoot. This may seem like a good thing, and it even looks good since the bull cane is in a perfect spot to renew the dead cordon, however this isn't the case. Bull canes are not winter hardy, because they wont ripen off properly and have big buds, and don't necessarily produce quality fruit. Therefore, these shouldn't be used as fruiting canes, but can temporarily be kept in order to keep vegetative growth in check (just like kicker canes). A goal is to keep fruiting canes smaller than the width of a pencil. 

The patterns on these leave are a result of a bud mutation. Just as bud mutations can change fruit color, so can they alter the chemical make-up of the leaves. These leaves are called chimeras and the white patches are due to the leave's inability to produce chlorophyll in certain areas. Whole shoots can be mutated white, which is bad for plant health because then they become nutrient sinks instead of sources. 

We decided to harvest half of our Marquette early in order to compare it to a second harvest in a few weeks. Of the two clusters per shoot, we alternated picking the top and bottom of each shoot in order to get a representational sample size. Typically the basal most cluster will be farthest along in fruit development since its complimentary leaf will have had the most time to mature (and it is closest to the cordon). Sometimes growers will let their basal clusters hang and remove them later for a reserve wine. These lugs were weighed, destemmed (in the destemmer to the right), fermented in the upside-down white buckets, pressed in our bladder press, racked, sent through malolactic fermentation (in order to add aromas and drop malic acid), reracked again and then aged. 

You can notice the difference in color of the berries that were exposed to the sun verses those that weren't. Fruit exposure to sunlight is important in increasing flanvanols (phenolic compounds which make up the wine's flavor, astringency, complexity, and aging potential). Additionally, exposed berries will have lower levels of acid (both tartaric and malic).  Lesson to be learned: find the Goldilocks. Learn how to expose fruit to the sun so that you can increase the flavors and colors to their maximum potential, while decreasing unpalatable acids.  However, if you leaf thin too much in the wrong places or at the wrong time, then berries may become sun burned and wither out. 

Week 14 (Sept. 16th - 20th)

This is Siegerrebe, my favorite eating grape that's supposed to be a wine grape. It is in the muscat family, so it has flavorful terpene aromas such as linalool and geraniol. We are making it into a sparkling wine. Yum!!

We have begun to replace all the rotting posts throughout the vineyards. We first walked down each row and pushed/pulled every post, listening to see if they cracked. If so, we'd mark them with orange tape. Afterwards, we pulled the staples out, cracked the post off the rest of the way, weaseled the old post stumps up with two shovels, widened the hole if needed, dropped a new post in and stapled the wires back to the posts. We have gotten pretty good at this art over the week. It takes us between 5 and 10 min/post, depending if they're caged like this one. Good thing the posts last close to 25 years!

We replaced a number of end-posts throughout the week as well. This entailed a bit more work: widening the angled holes, replacing anchors and strainers (the winch-like mechanism that I'm tightening here), and retying catch wires. We customized the trellises so that the fruiting wire was at a comfortable picking and pruning height. This happened to be around two and half feet, which allowed just enough space for a canopy of four and a half feet (roughly the shoot height needed to acquire 15 nodes, the number needed to support three clusters).

A Lacrosse news anchor and her husband stopped by on Friday to interview and film shots for a documentary that they are making on Minnesota wineries. It's fun to be in the action of such a novel industry! 

Week 13 (Sept. 9 - 13th)

John displaying the progress made in the roots over the past three months as they followed the water downward. Roots are composed of large arms and branches, root tips and root hairs. Roots are important for water and nutrient uptake, anchoring and carbohydrate reserves for dormancy. The majority of water/nutrient uptake happens in he white (fresh) roots while storage takes place in the roots that have hardened off and formed a periderm. 

This interveinal chlorosis is indicative of a magnesium deficiency. In this case the vine is a mutant and cant uptake the element (I know this because no neighbors displayed these symptoms). 

As we wait for more varieties to ripen we are occupying our time by removing discards. This task is on-going, as Peter is constantly assessing vines that have been planted over the past decade and weening them down to a select few. If he finds a vine that is promising (in growth habits, fruit size and flavor, disease resistance) he will mark it as a watch, and most likely remove its neighbors. Eventually watches are assessed and weened down to a select few. Peter will will give each of these vines a number. Numbered vines are then propogated vegetatively and planted in various locations throughout the vineyards, which have different soil textures, aspects, slopes, organic matter, etc. After years of closely monitoring the numbered vines Peter (and his boss Jim) will select the perfect vines to be named and patented. It is these that are then sold commercially. 

This is characteristic of the grape berry moth. It lays its eggs in the grapes so that the larvae can tunnel their way through berry to berry, forming a connective web between them. These affected berries generally will discolor and shrivel up after being the worm has chewed its way through them. We need to pick these "bad" berries out of the clusters after we harvest them. 

A pristine day for harvesting Edelweiss. This is a V. labrusca flavored grape (like Concord)  that was bred by Elmer Swenson in 1980. Though it was originally bred for wine, many people enjoy the taste and eat it fresh. All of the grapes here will be sold in the Arboretum's Apple House.