A reader sent this picture in and asked for identification. I think it to be Cytisus battendieri, otherwise known as Pineapple or Morroccan broom (and sometimes Argyrocytisus battendieri.) Truth be known, I am not familiar with this plant, but I am fairly certain I got it right. How did I do it from afar? Well first I established the plant's location to determine the host climate, then I determined the season that the picture was taken. In this case the reader told me that she had taken it at Kew gardens in England and I could see the date stamp showing the end of May. I could also determine that the plant was in the pea family (Fabaceae) by looking at the shape of its flowers. Its large glaucous-looking leaves suggested the possibility that the plant could be evergreen in some climates. Knowing the season of bloom, climate, color, family, and leaf shape and color I could easily do a plant search of May-June blooming, yellow-flowered, trees in the pea family and then I further refined the search based on the other known facts, leaf shape and specific location.
I came up with a fairly convincing match and further refined my search by researching to see if Kew, in fact, does have a specimen of this plant. They do and it is photographed widely on the internet. So does Hidcote. In my searching, I also discovered another interesting tidbit. A different species of Cytisus was discovered for the first time at Kew, and was named appropriately Cytisus x kewensis (Kew Broom) and is thought to be a cross between Cytisus ardoini and Cytisus multiflorus. All in all, the Brooms are fairly popular in England.
As for our pineapple broom, this plant can be grown in the US as well. Native to Morocco, Cytisus battendieri (named for French botanist, Jules Battendier) this plant does well in medium to dry soils and has seaside resistance. Hardy to USDA zone 7, and often evergreen this small tree can make a good screening plant. It also has the bonus of a nice fragrant smell, reminiscent of pineapples.
Did I get it wrong? If so let me know! Do you have more plant identifications to send? Bring it on. You can always send them to my Facebook page. I will be sure to get a response out and maybe even a blog.