Week 7 (July 15 - 19th)

Over the past few weeks I have noticed that in the mornings some vines have water droplets like this on the tips of their leaves. These droplets are generally found in the morning near the ground. This happens when the water is exuded from secretory tissues called hydathodes, pores found in aquatic and some herbaceous plants. It is most likely in these vines the water is being forced out of the hydathodes, instead of passively flowing out of the stomata, because the humidity near the ground is too high for evaporation to happen. 

This is a classic example of a vine trellised on the J-system. All of our V. vinifera grape vines, which you can see by the hanging bags were used in our breeding program, and non cold-hardy cultivars are grown this special way so that their canes and buds can survive the winter. Most of these species can only handle temperatures down to -8F. Therefore, every November J-system vines are unhooked from the wires, pruned and buried under dirt and straw. This vine happens to be a Riesling. 

One of this week's larger tasks was to tape the nursery vines to their bamboo stakes. This was a muddy, but fun, job that took us most of a day. During the process we also removed lateral shoots in order for the vines to focus their energy and nutrients into one main shoot. This "plumper" vine will be a greater storage of carbohydrates and nutrients for when these little guys are planted in the vineyard next year.

The goal of "combing" is to open up the canopy in order to increase airflow and expose the leaves within the canopy to the sun. This is important for the overall productivity of the plant, since any leaf that is in the shade is effectively a resource sink, not source. This practice of re-positioning the shoots also allows the fruit to be exposed to the sun, which will allow them to ripen faster. We are now starting to focus on the progress of the fruit growth instead of the shoot growth. We have made it through the lag period, meaning the fruit is starting to expand again.