Please send in your good wildlife photos to replenish the tank. Thanks!
Today we have a photo-and-text special on brambles from reader Athayde Tonhasca Júnior. His narrative is indented, and you can enlarge the photos by clicking on them.
Thorny issues
Once upon a time, so Charles Perrault (1628-1703) told us, a prince was out enjoying nature by merrily killing animals in the woods, when he spotted a hidden castle deep in the forest. The prince’s myrmidons explained that the castle housed a beautiful princess who had been cursed by an evil fairy; the young lady was to lay in a comatose state until awakened by a handsome prince. His Highness, who obviously had a high opinion of his looks, decided he was the person destined to break the spell. But getting to Sleeping Beauty wouldn’t be easy; the castle was surrounded by trees and a formidable obstacle that would have stopped a less determined hobbledehoy: a wall of brambles.
Having princely clothes ruined by brambles. The Sleeping Beauty, art by Arthur Rackham (1867–1939), Wikimedia Commons.’
Brambles or blackberries comprise many species that are difficult to tell apart; over 300 of them have been recognized in the UK. These related species are known as micro-species, and for practical reasons they are treated collectively as a species complex or as an aggregate group (abbreviated as agg.). So we usually refer to brambles as Rubus fruticosus agg.
Natives to much of Europe, brambles are valued fruit crops when grown as blackberry varieties, but they are also invasive in some circumstances. Their dense thickets are barriers to amorous princes and roaming livestock, and their thorns hurt animals and contaminate wool. Thanks to their vigorous growth (watch their shoots thrusting ahead), brambles can outcompete other wild plants and curtail the development of tree saplings; if left unchecked, brambles can quickly alter the species composition and physical structure of some habitats. For those reasons they are considered invasive weeds in Australia, New Zealand and the USA.
But as we have learned from many a definitive self-help book, problems are opportunities with thorns on them: several birds and small mammals nest or take shelter in bramble scrub. And their berries are food for sundry animals such as badgers, field mice, foxes, moths and voles: watch some of them having a nutritious fruit breakfast. Bramble berries are quite handy when other sources begin to dwindle in late summer and autumn.
A bramble thicket: barrier and shelter © Richard Humphrey, Wikimedia Commons:
But brambles have much more to offer; their open, bowl-shaped flowers, typical of the Rosaceae family, are easily accessible and produce large amounts of pollen and nectar, which are available during most of the season – usually from May to September in the UK. So a range of pollinators and other insects take advantage of these abundant and reliable food sources, from the European honey bee (Apis mellifera), which is one of the most enthusiastic visitors, to scarce species such as the brown-banded carder bee (Bombus humilis) (Wignall et al., 2020).
A welcoming bramble flower © Rosser1954, Wikimedia Common:
Brambles have a flexible approach to reproduction. They commonly propagate vegetatively (no seeds are involved) by deploying ‘runners’, shoots that take root when they are touching the ground; they can resort to apomixis, which is the production of seeds without fertilisation; or less frequently, they can use the familiar sexual mechanism of pollen deposition. This diversified strategy helps explains brambles’ complex taxonomy. Plants generated by vegetative growth or apomixis are clones, genetically identical to the parent plant. When they do occasionally outcross and produce seeds from fertilized ovules, the resulting offspring will have genetic profiles slightly different from the parent plant. Given time, these variants become species marginally different from each other, which spread out as clones and readily hybridise (Clark & Jasieniuk, 2012). Untangling these species is a job for a small tribe of patient, dogged taxonomists dedicated to batology (from the Ancient Greek báton, ‘blackberry’): the scientific study of plants in the genus Rubus.
Although infrequent, sexual reproduction is important for maintaining brambles’ genetic diversity, and here insects play their part by cross-pollinating plants. Among brambles’ many flower visitors, several bees and flies have been considered candidates for the job. But this list is biased because it leaves out insects we don’t normally see collecting pollen or nectar – the nocturnal visitors, i.e., moths. And they should not be neglected. Like many other plants, brambles produce nectar with variable concentrations of sugars during the day, and their highest output happens to be from late afternoon into the evening. Such sugary bounty wasn’t likely to go unnoticed by the night shift wanderers. Anderson et al. (2023) reported a range of visitors to brambles flowers during the day (flies and bees, mostly); but at night, moths were almost alone in dropping by for a sip of nectar. But there was more; moths visited fewer flowers per hour than diurnal visitors, but they deposited more pollen grains on stigmas. That’s an important finding. Flower visitation is often – and incorrectly – assumed to be pollination. In fact, many visitors avoid pollen altogether, or manage to remove the pesky yellow grains from their bodies. Pollen deposition is a well-tested method to evaluate who is pollinating what.
A tobacco hornworm (Manduca sexta) depositing pollen on a Colorado Springs evening primrose flower (Oenothera harringtonii) © Smith et al., 2022:
So here we are. Blackberry lovers notwithstanding, brambles are generally despised components of our flora, even though they play an important part in supporting pollinators and other animals. These brambles’ customers in turn may depend on secretive moths for the sexual reproduction of their hosts. As is often the case in nature, the plot is considerably thicker than it looks.
Among the brambles, by Valentine Cameron Prinsep (1838–1904), enjoying luscious berries © Stephen Craven, Wikimedia Commons:
Great article highlighting the often-overlooked value of brambles in supporting pollinators and other animals. It’s a great call to action to send in good wildlife photos to replenish the tank.
founder of balance thy life https://balancethylife.com
Here in the Pacific Northwest we have an invasive blackberry that we both love and hate. The plant grows seemingly without limit along roadsides and streams and in abandoned fields. If it infests your garden it’s difficult to eradicate. The berries are huge and delicious, and people stop along highways in late summer to collect them—even as cars speed dangerously by. The seeds are large, but they are tolerable and can be filtered out if necessary. To illustrate how invasive they can be, there are signs along the road that advertise a service that will eradicate them. The sign says:
Blackberries Killed—Permanently!
I love the implication that there is a kind of death that is temporary. I’m told that one way to kill them (permanently) is with a flamethrower, but I doubt that a flamethrower is effective (permanently), as the underground runners just keep creeping along as if nothing happened.
More here, including a recipe!: https://mynorthwest.com/1466755/invasive-blackberry-specie-himalayan-blackberries/
In my experience, the only way to ensure blackberries are eradicated is to first cut them down by any means necessary, including, I suppose, a flamethrower…but one of the most interesting and cutest methods I’ve seen is to employ goats. They eat almost anything and can chomp a plot of blackberries to the ground. In a crucial second step, the soil is turned over to a considerable depth; to expose the roots. The exposed soil must then be allowed to dry out; if it rains you’ll have to start all over again. Being the PNW, that requirement means careful meterological foresight and keeping all your fingers crossed.
Needless to say, a serious infestation of the delicious blackberry bush is hard to deal with.
Yes! I’ve seen the goat trick used, too. The space is fenced off, goats are brought in, and the magic happens. Those goats must have buccal cavities that are highly resistant to pain and damage. The blackberry thorns are scary sharp!
When I lived in Vancouver many eons ago there was a large patch of blackberry behind our house.
I would always wear heavy protective clothing when picking the berries and I always carried secateurs to cut my way out when needed, which was often.
Another NW resident here. Around our property it’s a yearly chore keeping the blackberry bramble at bay. I’ve also heard of the flamethrower method…probably better than poison. I’ve also heard about renting goats. That would be fun. One thing I’ve noticed is black bears don’t seem to be bothered by them. They’ll run right through a bramble thicket without slowing down.
Informative and humorous as always – thanks!
Thanks for this fun post Athayde. I have a lot of experience with blackberry brambles. And as you noted, there are many critters who live in there. I’ve seen bunnies, birds of all sorts, shrews and snakes. Star-nosed moles like to burrow on the outskirts of our brambles as well.
Always a great read.
One of the things I plan to do in case of a zombie apocalypse is to develop a shelter surrounded by yards and yards of brambles, with a secret tunnel in and out.
Good information here. As much as I enjoy blackberry jam, most of my interactions with them involve using the bush hog to try to keep them from taking everything over completely.