Friday, May 30, 2008

Semillon

The history of the Sémillon grape is difficult to establish. It is known that it first arrived in Australia in the early 1800's. It was once considered to be the most planted grape in the world, although this is no longer true
Sémillon is relatively easy to grow and has vigorous vines which can easily produce ten to fifteeen tonnes of grapes per hectare if not kept under control. The grape berries are thinned skinned, small, round to oval and greenish colored. It is fairly resistant to disease, except for rot. The grape ripens early in warmer climates. Due to the thin skin there is a risk of sunburn in hotter climates as well as splitting after heavy rain. It is best suited to areas with sunny days and cool nights.
Sémillon is one of only three approved white wine varieties in the Bordeaux region. The grape is also key to the production of sweet wines such as Sauterne
In Bordeaux it is blended with Sauvignon blanc and Muscadelle. When dry, it is referred to as Bordeaux blanc and is permitted to be made in the appellations of Pessac-Léognan, Graves, Entre-deux-mers and other less-renowned regions. In this form, Sémillon is generally a minor constituent in the blend.

However, when used to make the sweet white wines of Bordeaux (such as those from Sauternes, Barsac and Cérons) it is often the dominant variety. In such wines the vine is exposed to the "noble rot" or what may be called the "positive affect" of Botrytis cinerea which reduces the water content of the fruit, concentrating the sugar present in its pulp. In this case Botrytis cinerea causes the grapes to shrivel and the acid and sugar levels to intensify.
In Australia, Semillon is produced both as dry unwooded and wooded table wines and as botrytis affected "stickie" dessert wines. In the Hunter Valley of New South Wales, Semillon is made into an initially subdued unwooded wine of relatively low alcohol (10-11%). But with bottle age it developes into a full flavoured toasty honeyed wine which is a style unique to Australia.
This year we made our first 100% Semillon from our relatively young vines.
It has been in the tank now maturiung for 4 months and is just starting to develop the typical Semillon nose ie. grass/hay/apples. Alcohol level is around 10.5% and intially we were quite concerned at it's high acidity. But on storage there has been quite a precipitation of tartrate and TA has dropped and pH has increased. We will be ready to bottle in a month or so.



Monday, May 26, 2008

Moths

We have our fair share of moths that are attracted by our lights.
One of the most famous visitors is the bogong moth. Last year they arrived in their millions and our windows were covered for nights on end.
They have been known to completely shut down the electical circuts of multi storey buildings, shutting off air conditioning units and standing passengers in lifts. In our captital city, Canberra, it became necessary to turn off all public building and street lighting to prevent blackouts.
As larvae, the insects live in the soil across southern Queensland and the western plains of NSW. In spring the moths follow the Great Dividing Range, heading to the Snowy Mountains to avoid summer's heat. There they hibernate in caves, up to 17,000 every square metre.
Aborigines once visited the caves to collect the moths, which are rich in protein and fat.
According to one study, 100 grams of bogong moth abdomen has three times the fat, and almost twice the kilojoules, of a similar portion of a Big Mac.
On their southern trek westerly winds often blow the moths off course and over the mountains and into coastal areas. This is when we see them but thankfully not every year.
A few weeks ago we had another moth visitor I had not seen before. They were not in huge numbers but were the size of a small bird. They stayed a few nights and then disappeared.
For identification I sent off a picture to the moth guru at the University of Sydney who said it was Chelepteryx chalepteryx or the white stemmed wattle moth.

He was so impressed with my picture it is now on his web site.
It is considered a large moth with a wing span of an adult male up to 10cm (4 inches).
We can only guess that the caterpillar feeds on the local wattle trees (Acacia sp.) that abound in this area.