Native bluebells and other bulbs

David Beeson

Our native bluebell (Hyacinthoides non-scripta) is found widely around north-west Hampshire. The UK has 70% of the world population of this plant and we can rightfully claim plenty of that locally.

Like many of the plants that grow under deciduous woodland the bluebell comes into leaf and flower early in the year. If they didn’t, they would not survive because the tree canopy would close over them, and it usually absorbs 90+% of the sunlight.

With an early leafing and flowering the wind pollinated plants have enough breeze for the distribution of their light pollen and the insect-reliant species can make use of the early-flying bumbles and flies. So, deciduous woodlands are at their ground flora best early in the year.

Bluebells are often accompanied by dog’s mercury and wood sorrel. In the lighter swathes there will be primroses but little else thrives.

When the bluebells’ seeds are shed they fall adjacent to the parent plant and seem to be ignored by the usual animals that disperse seeds. Germination occurs in the autumn when temperatures begin to drop and the rains pick up. Interestingly, bluebell seeds germinate within the leaf litter and begin putting down their initial root before the first frosts. Often this root is contractile, pulling the tiny seedling down into the soil where it is less likely to freeze.  

Over the next 4 to 5 years, the bluebell’s contractile roots pull it deeper down into the soil, taking it out of the reach of predators and frost. This also takes them farther away from the nutrient-rich surface layers. What’s more, the roots of older bluebells are rather simple structures. They do not branch much, if at all, and they certainly do not have enough surface area for proper nutrient uptake of phosphorus. This is where mycorrhizae come in.

Bluebells partner with a group of fungi called arbuscular mycorrhiza, which penetrate the root cells, thus greatly expanding the effective rooting zone of the plant. Plants pay these fungi in carbohydrates produced during photosynthesis and in return, the fungi provide the plants with access to far more nutrients than they would be able to get without them. One of the main nutrients bluebells gain from these symbiotic (mutualistic) fungi is phosphorus.

It takes at least five years for a bluebell seed to grow into a bulb. Hence this species expands its range or moves to new locations very slowly.

So, if you spot a mass of blue in a woodland it usually indicates it as an ancient woodland. (Ancient Woodlands are defined as those which have existed since 1600AD.)

In the cooler and wetter parts of the UK bluebells are often encountered in more open habitats.

The bluebell is, however, under treat.

Gardeners have planted the larger, more vigorous Spanish bluebell into their gardens and its pollen has inevitably been passed to the native species and produced viable seeds and offspring. This is a new ‘crossed or hybrid’ species. Additionally, these hybrids can cross themselves with more native types or Spanish bluebells (back crosses) producing a ‘hybrid swarm’ of different variations.

Not only are there now these crossed bluebells in our woodland, but the invaders can be pink or white in flower colour. [Natives produce very few white flowers and almost never pink-flowered plants.]

The hybrids seem to have the best bits from both parental types, so loved by gardeners and can out-compete the finer native. In the 1960s there were less than a dozen spots in Southern England where these hybrids could be seen in the wild, now they can be discovered almost everywhere in England, and lowland Wales and Scotland.

One of the most delightful things about a wild walk in May is the special smell of wild bluebells … that could be soon a historical smell, as the hybrids lack the aroma.

Remember, picking bluebells is allowable with the landowner’s permission, but only for personal use and never allowed on nature reserves or council-owned land. It is illegal to uproot a wild plant without permission of the landowner. Seed collection is normally allowed.

Bluebells synthesise a wide range of chemicals with potential medicinal properties. Like almost all perennial plants, they contain biologically active compounds (toxins) that may provide them with protection against insects and animals. Archaeological evidence has shown that Bronze Age people used bluebell glue to attach feathers to, or ‘fletch’, their arrows.

For bluebells visit the extreme south of Harewood (e.g. Upping Copse), the wood adjacent to the John Lewis garden centre near Leckford and Combe Wood north of Linkenholt.

Often associated with bluebells is the wood anemone. It does not grow from a bulb or corm but from swollen roots – rhizomes. Anemone nemorosa is to be found in deciduous woodlands and hedgerows.  It produces solitary flowers in spring.  Like old man’s beard, it is a member of the buttercup family – the Ranunculaceae.  It is sometimes called ‘windflower’ because of the way the flowers shake / move in the wind. The plant is poisonous; it contains protoanemonin, an acrid (and bitter) oil – formed from the glycoside, ranunculin. Protoanemonin can cause severe skin irritation and gastric disturbances if ingested.

Wild daffodils are found in profusion in Wiltshire’s Cranbourne Chase. In Hampshire they are uncommon, although they are found in the New Forest, to the west of Romsey and our one local site: near Longparish.

The ‘golden triangle’ around Newent and Dymock (north-west of Gloucester) is famous for its wild woodland daffodils. A 10-mile footpath known as ‘The Daffodil Way’ runs through woods, orchards and meadows, in which the wild daffodil is rarely out of sight.

The wild daffodil is smaller than horticultural varieties, with paler petals and a deep yellow trumpet-like tube. The leaves are grey-green, thin, long and flattened. It grows in groups so can be quite an impressive sight. It usually enjoys damp woods, fields, grassland and orchards. Their distinctive pale-yellow blooms can be seen at their best in March and April. (Recently there has been a shift in the average flowering date of daffodils and hawthorn (Crataegus monogyna). In the 1980s daffodils commonly flowered around the 12 February, but by 2008 this date had shifted to the 27 January, 16 days earlier.)

After flowering leaf and root senescence sets in, and the plant appears to be ‘dormant’ till the next spring, conserving moisture. However, the dormant period is also one of considerable activity within the bulb building the flower and leaf structures for the following year. It is also a period during which the plant bulb may be susceptible to predators. Like many bulb plants from temperate regions, a period of exposure to cold is necessary before spring growth can begin. This protects the plant from growth during winter when intense cold may damage it. Warmer spring temperatures then initiate growth from the bulb.

White Spanish bluebells. If you look closely you will find many plants are part hybrids of English and Spanish bells.

As with the bluebell, seeds spread slowly.

Once the leaves die back in summer, the roots also wither. After some years, the roots shorten pulling the bulbs deeper into the ground (contractile roots).

In my own garden I had built up a colony of many hundreds of wild daffodils beneath two 100+ year old walnut trees. Within two years all had died – presumably by being eaten by nematodes or cockchafers or infected by fungi. They are now slowly recovering on the outer limits of their previous distribution.

The leaves, stems, seed pods and bulbs contain toxic alkaloids. If eaten they can cause dizziness, abdominal pain, diarrhoea and occasionally also convulsions. The toxins are usually most concentrated in the bulbs. Rather surprisingly, daffodil bulbs have been eaten on occasion after being mistaken for onions. The sap can cause dermatitis, and the leaves are poisonous to livestock.

Are snowdrops native wild bulbs? No one is certain. The ones in Harewood seem to be associated with previous accommodation. Regardless, in late winter they are a joy to behold and any early-year bumblebees are content to take their offerings of nectar and pollen.

Lily-of-the-valley is a native that is not found naturally near Andover. To find it search in the northern New Forest or on Silchester Common. It does occur near Winterslow across the Wiltshire border.

Meadow saffron (Colchicum autumnale) is a rare crocus-like flowering plant found wild near Appleshaw. As with most bulbs, it is highly toxic.

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