It isn’t perfect, but it is improving. My alfalfa seedlings are recovering from the long dry spell – on the other hand the deer are discovering them and trying to graze them down. NOAA shows this map for soil moisture:
This next map shows precipitation during August – again, it isn’t perfect, but coming out of a drought it shows us on the fringe of recovery – far ahead of southeast Washington down through most of Oregon and California.
It may be too early to say that we dodged the bullet for another month or so – but at least the recent precipitation has moved us to a place where we can dodge. At least the long-term predictions are pretty much back to normal probabilities of precipitation:
These maps, taken from NOAA’s website show what the early August rains did to change the moisture stored in our soil. For us, the rains lifted the pond by almost an inch and a half. They didn’t add enough soil moisture to fill the cracks in the vertisols, or create any puddles – but we have hopes that the slight increase in soil moisture will help at least some of the little alfalfa plants survive. At any rate, the NOAA website demonstrates how much more information on weather is available now compared to a half-century ago. The difference between July 31 and August 9 is impressive – though we will probably check again next week to see how the soil is doing.
Stepping outside after this weekend’s much-needed downpours, I was met with a familiar fragrance. The smell of the earth after rain, sometimes called “Petrichor”.
This is a fairly modern word, cobbled together by a couple of scientists in 1965. It’s derived from two Greek word roots. Petra (πετρα) meaning “rock” and ichor (ιχωρ) meaning “blood”. But ichor is usually a special sort of blood – the juice that flows in the veins of a god or giant, perhaps a monster, not a mere mortal.
Petrichor’s scent is strongest after rain beats down on hot, dry soil. When rain pummels the earth, it stirs up waste from tiny soil bacteria called Actinomycetes… tossing tiny particles of something chemists have named “geosmin” into the air.
Interestingly enough, this same compound that brings us that lovely post-rainstorm aroma is also responsible for strong earthy flavors.
If you’re not fond of those earthy flavors, consider adding an acid during cooking (such as vinegar). This will cause geosmin to break down and give you less-fishy tasting fish or vegetables that taste less of dirt.
On a more entomological note, mosquitoes are attracted to geosmin’s smell in preparation for laying their eggs. A number of entomologists and chemists are currently experimenting on traps using geosmin extracted from beetroot skins.
I look forward to seeing how geosmin trap technology develops – but I suspect it’d be quite possible to come up with a homemade trap based on the same principles that’d work well. After all, if we can collect and destroy many mosquito eggs, we should see some dint in next years’ mosquito populations.