Tag Archives: nitrogen fixation

More wild flowers

I keep seeing herb robert lining my route to work and in the hedgerows along my regular footpaths. It’s a member of the Geranium genus and is found in hedgerows, woods and on disturbed ground


Herb robert – Geranium robertianum

I’m a tad confused by this plant because it has all the normal attributes of herb robert; the pink flowers, leaf shape, hairy buds and stems, but this one has the same bud shape as a cranesbill and a quick web search hasn’t yielded another image of herb robert with seed pods shaped like this. (So if I’ve made a taxonomic error please let me know!). Herb robert smells quite unpleasant and has been used as an insect repellant.


Dandelion – Taraxacum officinale

These pictures were taken a few weeks ago and at that time they were loaded with insect life, this danselion has six flower beetles (Oedemera nobilis) foraging on it, and it wasn’t at all unusual to see flowers in the meadow with this many bugs and more feeding on them.


White clover – Trifolium repens

Clover grows abundantly in grassland. It is pollinated primarily by bumble bees but as bumble bee numbers decline it has become a major source of nectar for honey bees, therefore beekeepers became important people for cattle farmers who grow clover as a fodder crop for their livestock.

Jack go to bed at noon – Tragopogon pratensis

The lovely yellow star of ‘jack go to bed at noon’ is so named because the flowers open early in the morning and close up again at noon. It is also known as ‘goats beard’ and is a native annual in the UK. It has a milky latex sap which, according to Wiki, children from the countryside in Armenia make bubble gum from. It has a wonderful seedhead which is much bigger than than the dandelion and has fewer larger seeds.


Jack go to bed at noon seedhead

As with alot of other wild flowers, they are rampant just now because of the warm wet weather and are numerous in fallow fields and hedgerows.

A jack go to bed at noon seedhead with a closed flower behind it at the edge of a field

Also common around Cambridge right now is the birdsfoot trefoil. The flowers here are a gorgeous golden yellow but can also have red or orange which gives them their other common name: bacon and eggs.


Birdsfoot trefoil – Lotus corniculatus

Birdfoot trefoil is a legume which means it can actively fix nitrogen from the atmosphere. It can do this with the help of symbiotic bacteria which colonise root nodules and convert inert atmospheric nitrogen into ammonia, a form of nitrogen which plants can use. This ability makes the legumes a natural fertiliser because nitrogen is required by all plants, but unless they can fix it in this way they are reliant on alternative sources in the soil. Poor soil can be boosted by the application of other fertilisers such as good old fashioned manure, or more recently ‘NPK’ (Nitrogen/Phosphorus/Potassium, ‘K‘ being the chemical symbol for potassium). Or, when cycles of crop rotation are used, one of the crops used may be another legume, such as peas, which can help to replenish nitrogen levels in the soil naturally.