There is a wonderful piece by the Kitchen Sisters on US National Public Radio about the history of dates in California — and about plant exploration, politics, and people.
There are about 3400 ha of date palm in the Coachella Valley, a Southern California desert. Here is a road side view (note how you can you can estimate the growth rate by comparing with the 2007 street view photo) and here is another grove. Wikipedia says that that the Spanish introduced the date palm to lower California (Mexico) in 1765; but Walter Swingle gets the credit for bringing the plant to the USA (see this letter by David Fairchild). In 1903 he collected Deglet Noor in Biskra, Algeria, and in 1929 he collected the prized cultivar Medjool in Morocco.
Coachella date grower Patricia Laughlin has this to say about that:
When the Medjool dates came in, there were only nine offshoots that all of the present trees come from. These medjools came from the oasis of Bou Denib. It’s been wiped out by a disease in Algeria and Morocco. We have sent back good plant stock to return to those areas from which they originated. My husband and I visited. It’s over the Atlas Mountains from Marrakech — out really in the desert. When we got to Bou Denib, the mayor came out to greet us. It was a big occasion. And he said why would anyone from the United States want to come to Bou Denib? We had worked with the Medjool dates for so many years and to see where they originated was very meaningful for us.
There is lots about Swingle in Fairchild’s “The World was my Garden”. He was a contemporary of Fairchild and a bit of a polymath with a later focus on citrus. When I read of `biopiracy’ and how evil the British, Australians and the rest were I think of the very fine work in plant introduction done by the US plant explorers, more than 100 years ago, that transformed US agriculture. Interesting that the famous PI numbers (=plant introduction) was later changed to plant `inventory’: an almost meaningless term for getting your agriculture up and running by importing the very best (no random collecting here) from other regions.
“… only nine offshoots that all of the present trees come from …” – reminds me of the history of race horses which also came from but a handful of imported Arabian animals. And has me wonder if we should not go back to the originals habitats of our current crop varieties and try and expand the gene pool somewhat to avoid potential disastrous disruptions?
That’s what plant breeders do all the time. Not sure about horse breeders.