Tue 2009-10-06 
A willow herb seed head. These develop from these:
which, in turn, develop from these:
This plant was growing in the long grass and was rather small compared with the great hairy willow herb (Epilobium hirsutum) that grow beside the lakes, so I don't know whether it was the same species. I will just call it Epilobium sp. for the time being.
Photos taken in Whiteknights Park, Reading University grounds, Reading, UK, on 2009-09-09.
Tue 2009-09-22 
Larger bindweed, Calystegia sepium, also known as white bindweed, or hedge bindweed. Not to be confused with field bindweed, Convolvulus arvensis, which is smaller and often has pale pink stripes on its petals.
Photo taken in Whiteknights Park, Reading University grounds, Reading, UK, on 2009-09-10.
Sat 2009-09-19 
Sneezewort, Achillea ptarmica. Sneezewort is similar to the closely related yarrow (Achillea millefolium) but has fewer largish isolated flowers instead of the many small flowers that are clustered into inflorescences on yarrow. Also, the leaves are not feathery like those of yarrow, but are are straight and narrow:
Photos taken in Whiteknights Park, Reading University grounds, Reading, UK, on 2009-08-12.
Tue 2009-09-08 
Bristly ox-tongue (Picris echioides), an awesomely prickly plant, much more so than the spiny sow thistle (Sonchus asper) that I originally thought it must be. Really awkward to hold still in a wind when you are trying to photograph it.
A quick search of Google Images suggests that the reddish colour in the petals is unusual, they are normally pure yellow.
Photo taken in Whiteknights Park, Reading University grounds, Reading, UK, on 2009-09-06.
Sun 2009-09-06 
Common agrimony (Agrimonia eupatoria) growing in the long grass in Reading University grounds. The flower spikes can grow to over 50cm tall. When the flowers wither they develop into reddish seeds which are covered in little hooks, rather like burdock only smaller:
When I finished taking these photos I discovered four or five of these seeds attached to the hairs on my arm. This plant had several flower spikes and several seed spikes at the same time.
The leaves of the plant look like this:
Photos taken in Whiteknights Park, Reading University grounds, Reading, UK, on 2009-09-05.
