This is a great time of year to admire the Prunus species on campus. Not only are the ornamental cherries wow-ing us with their blossoms but the naturalised species are also in flower.
Cherry laurel in flower in early April
Parts of the wilderness are dominated by Cherry laurel (P. laurocerasus). This is an evergreen shrub that reaches a height well over my head. It has racemes of white flowers in April. Continue reading
Posted in Flowering Plants, Plants, Rosaceae
Tagged Bird cherry, Blackthorn, Cherry laurel, Cherry plum, Portugese laurel, Prunus, Prunus avium, Prunus cerasifera, Prunus laurocerasus, Prunus lusitanica, Prunus padus, Prunus spinosa, Wild cherry
Dandelions (Taraxacum officinale agg.) get a variable press in Britain.
Beauty or weed?
They are, arguably, beautiful flowers (actually groups of tiny flowers as Dandelions are a member of the Asteraceae family) but my sister wages war on the species as her most hated weed. I guess they can look messy when you have a mixture of flower-head buds, flower-heads, seed heads and old stems that have shed their seeds, but a road-side verge full of golden dandelions has got to be as bold and cheerful a sight in spring as a verge full of golden daffodils!
So why do gardeners hate them so much? Maybe because they are difficult to remove or relocate. Some self-seeding wild flowers make a welcome addition to the garden and are easily removed from the ‘wrong’ place or once they are past their prettiest stage. Not so the dandelion.
Regrowth from a cut Dandelion root.
The dandelion’s tap root goes extremely deep, enabling it to compete effectively for nutrients and water. But, for some reason, the root is less woody than is general for tap roots, so it readily snaps when pulled. The lower section that remains in the ground, has the ability to regrow even if none of the plant stem material is left behind. A small ring of new shoots develop around the broken root surface and each of these shoots pushes up above ground so that one shoot is now four or five… or seven or eight. That’s why my sister hates them! That and the fact that every amazingly engineered dandelion clock is a ticking bomb of potential new recruits to the population. The seeds will seek out and find the bare soil where weeds have been removed or ground has been prepared for vegetables or chosen flowers.
Children, however, are much more likely to pause in wonder at the bright jewel of the flowers, or enjoy the fun of blowing away the seeds of a clock – even if breaking the stem and getting the white sap on your hands is supposed to make you wet the bed!
Stars in the grass
How’s this for a child’s-eye view:
Yellow and shining
Fluffy disc of gold upturned
A star in the grass.
Cassie Newbery – aged 11
Upright Ginkgo leaves
This week, while collecting samples of Ginkgo leaves from the tree behind Whiteknights House, I noticed that the remaining leaves seemed to be caught upright in the lengthening grass.
I assumed to start with that the leaves were being held in place by the grass but closer inspection showed that this was not the case.
The petioles (or stalks) of the leaves were actually within the soil as if they’d been pushed vertically in. ??? One leaf had its entire 5 cm of petiole within the soil! Continue reading
There is nothing better than the great outdoors for a day of vegetation surveying. Vegetation surveying can help track environmental change, and can form an integral part of the biodiversity assessment of a site. In addition, the surveyor can make predictions regarding other biodiversity on the site i.e. if you have Elms (Ulmus sp.) on site, you might have a colony of White letter Hairstreak (Satyrium w-album), which can help make important site specific management decisions. Also, the knowledge of plants has helped entomologists record the host plants of invertebrates, over several centuries, allowing us to calculate that the English Oak (Quercus robur), supports the most species of insect in the UK. Continue reading
Behind the greenhouses in the Experimental Grounds is a patch of mostly bare ground that has clearly been well-trodden by naturalists over the past year or so. It’s the site where mousetail was rediscovered on campus last spring, and perhaps thanks to experimental cultivation in the past is home to an interesting assemblage of other arable weeds as well. Or at least it was. Unfortunately, recent building works have necessitated the passage of heavy machinery over part of the patch, so for the moment it is an unrecognizable mud-bath. That said, a bit of robust disturbance might perpetuate the existence of early-successional vegetation on the patch and ensure that some other goodies turn up in the near future once construction is complete.
On a visit to the patch last July I kept spotting ground beetles moving across the bare, sunbaked soil, and I subsequently dug in a couple of pitfall traps to see if anything interesting was living alongside mousetail et al. The resulting catch was until recently mostly un-inspected; however, a trip on Saturday to the annual BENHS Carabidae identification workshop provided the appropriate motivation to fish them out.
Harpalus affinis by Udo Schmidt on Flickr (CC BY-SA 2.0)
A selection of acrocarps growing on concrete: Orthotrichum cupulatum, O. diaphinum, Grimmia pulvinata, Tortula muralis, Syntrichia montana, Bryum argenteum and B. dichotomum. Image by D. Morris
3. Saxicolous Mosses
This is the fourth in a series of posts exploring the mosses and liverworts (bryophytes) of Whiteknights campus. My first three posts described the rich flora of bryophytes growing on trees (epiphytes) on campus. In this post attention is turned to mosses growing on stone, including walls and other man-made rock-like surfaces. Continue reading
A mat of the very common thalloid liverwort Metzgeria furcata. Image by D. Morris
2. Epiphytic Liverworts
This is the third in a series of posts exploring the mosses and liverworts (bryophytes) of the Whiteknights campus. My first two posts introduced some common and not so common mosses of trees (epiphytes), and this post will address the liverworts to be found in association with these on campus. Liverworts are not very well represented in most parts of lowland England so one need not fear being overwhelmed by species. Continue reading