Nature blog: birds and their nests at CAT

by Rennie Telford

Morning Everyone, Nest building is well under way for a lot of birds now and you can see them busily collecting various building materials all over site. The nuthatch which looks as if it is going to take up residence in the bird-cam box above the restaurant is continually carrying out rather unnecessary repairs to the box–patching up gaps and crevices with mud and debris. In natural nest sites like holes in trees the nuthatch is one of the only British birds which will plaster up the entry hole to make it as small as possible to maximise security for its young. Several of the many nest boxes around the quarry are being investigated by all the usual suspects–blue tits, great tits, robins etc and it looks like a bumper year for insects so lets hope lots of successful broods will be raised. I was watching a female Blackbird hopping around in the undergrowth collecting twigs, feathers and bits of leaf but she seemed inordinately fussy and would pick up a likely looking item only to spot a better piece, try to pick that up as well and end up dropping both of them and then gaze quizzically at them, undecided which one to choose. I presume she will build a nest eventually but it may take her some time!

War on slugs. Here are some the suggestions for dealing with slugs from our Facebook and twitter friends

by Roger Maclennan Gardens

I heard a way of dealing with them the other day, which has stayed with me….cut them in half and put on bird table……at first i was like yukkk but then , if I want to kill them , just do it…..then at least they are food for others, not poisened or drowned etc……..but can I?

Spray the Homeopathic remedy Helix Tosta 6x on the plants once – in three day’s they’ll be slug free.

Breed ducks, let them roam the garden, eat the ducks.

beer traps! bury a jar in the soil so the top is just above dirt, then half fill with beer. come back in the morning and it will be full of drowned slugs.

I’ve not tried it personally, but our ecology lecturer at uni had a lot to say about learning to identify different species of slugs; apparently leaving the carnivorous ones alone is a good idea, as their main diet is other slugs!


pick um up and feed them to me chick chicks, they love a slug or a snail, its both gross and entertaining watching them fight… makes nice eggs too,

Eggshells around plants keep them at away from them. I also heard but have not tried yet, putting wood out at night in the garden, the slugs get onto the wood, then you feed them to your chickens in the early morning.

A big hammer??

course if you have chickens and are trying to grow anything then slugs are the least of your problems. They are so smart, havnt found a way to proptect seedlings that they havnt found a way round, latest is using old 2 litre coke bottles, just waiting to finnd them dug up or something bizare, ill have to take some picks…

Coffee grounds are supposed to be good at detering them. I also heard that mowing the lawn on a damp night is good at disposing of slugs but perhaps not good for the neighbours! LOL. Sharp grit is good too, Oh and dumping them in the green weelie bin when desperate…… Only the small ones as the big ones are detritus eaters.

the copper thing never works for me so I’m afraid I use the microbes.

finding what the slugs *don’t* eat, and growing that instead!

They don’t like plutonium, so err.. do nothing.

upturned orange skins (the hide underneath)
also a copper wire apparently gives them an electric shock, but could be expensive.
and carrying on from Tims carnivorous point, apparently slugs with tiger patterned backs eat other slugs.

Toss em over into next doors garden:-)

I’ve heard that garlic powder sprinkled liberally around delicate plants can be very effective…

My friend swears by vaseline mixed with salt smeared round the sides of pots and raised beds.

Hair clippings (get from the hair dressers) and bran – they eat it and it dries them out. Of course only good in dry weather.

Essential oil of garlic – couple of drops per watering can of water. They hate it and will go next door all by themselves.


They dont travel across water so you can make a moat if growing in pots.

Scissors in the moonlight.

“Nemaslug” microscopic nematode worms that eat the slugs from the inside which I think is as fitting an end as they deserve. They come as a beige powder in a sealed plastic pack and you add it to a watering can. I don’t know why Nemaslug is not available in shops, but I buy it from

Coarse sandpaper round your pots and raised beds. They don’t like slithering over it!!

If it rains in the daytime and stops when it gets dark, grab a torch and a brick and go for it! Two or three rounds of that (getting the little pink ones, they seem to be the most grief) and they’ll all b***er off!

CAT gardener Roger takes over the blog.

by Roger Maclennan Gardens
Hi all. I’m Roger, head gardener at CAT. This week I’m taking over the blog. I’ll be posting stuff about what it’s like working in the gardens here. And also some useful tips and information for all you gardeners. Here’s a quick video to introduce me and the gardens.

Dave Hood: Lecturer MSc Renewable Energy in the Built Environment and CAT Engineering Department

by Dave Hood Lecturer MSc Renewable Energy in the Built Environment and CAT Engineering Department

davehoodI’m a lecturer or the Renewable Energy masters at CAT and an engineer in the engineering department here . This week I’ll be taking over the blog, Facebook and Twitter. This week at CAT the renewable energy masters students will be here for a residential week of lectures and practicals. During the week I’ll be updating you on what we’re doing. I’ll be introducing you to some of the topics we’re covering this week and some of the students. I’ll try to give you an insight into what it’s like studying the theory and practice of renewable energy. I’ll try to give you a flavor of what it’s like to study at CAT and learn using our hands on practical teaching methods. Before coming to CAT I was involved in development work in Nepal installing small-scale solar photovoltaic systems. I was also a renewable energy engineer at the Sunseed project in Spain.

Floating Tomato Rafts: an integrated Solution to Food Production and Sewage Treatment?

by Grace Crabb Biology Department

grace_nologoOur department at CAT don’t just do woodlands. We are busy in the woods at the moment because it the management season, but just as much of our time is taken up managing the water and sewage at CAT. Our area of expertise is ecological sanitation and nutrient recycling, as well as low carbon solutions to drinking water, and water efficiency in the home.

I have recently completed an MSc at Cranfield University in Community Water Supply and sanitation. Here is the abstract from my MSc thesis on floating tomato rafts.

tomato_raftInspired by the philosophy of natural sewage treatment and human nutrient recycling, an experiment was conducted by floating rafts of tomato plants on the surface of mini sewage ponds. The rafts were made from recycled plastic components, creating a locally appropriate and easily replicable design. The hypotheses were a) that the rafts would produce a viable crop of tomatoes whilst at the same time removing nitrogen from the effluent and b) that a biochar substrate within the bed would be more effective than sand at absorbing ammonia and causing elevated levels of nitrification due to the air trapped within the lattice structure of the char.

tomatosAmmonia-N, nitrate-N and pH concentrations were tested at 5 day intervals using a photometer. For a month, continuous and unprecedented heavy rain and high winds had increasingly negative consequences on the growth of the tomatoes, causing significant stunting through water-logging and early blight. Therefore, the experiment was re-established in the shelter of a polytunnel and data collection began on new effluent. This change in location created a surge of growth in the plants. However, due to these problematic beginnings and shortened timeframe for water tests and growth data collection, results proved inconclusive. Despite a lack of statistical significance, observed trends in the data strengthened the hypotheses and therefore justify further study. Subsequent experiments should not allow mini-ponds to be exposed to heavy rain and winds. Also, in further experiments the tomato plants would benefit from a higher sunlight to raft ratio on the surface of the pond so that algae could accumulate and aerate the surface waters.

The biochar debate

by Grace Crabb Biology Department

grace_nologoBiochar has been hailed a potentially major contributor to climate change mitigation, so we thought we’d have a play with it at CAT.

We make biochar here at CAT in a retort, a system that recycles the gases (CH4 and C))preventing them from returining to atmosphere. Our home made retort is much faster than a normal ring kiln charcoal burn and produces more kilos of product. Actually we make mostly woody char that we then use as a sewage treatment medium in our constructed wetlands. This can then be added to the soil for experiments. Sometimes we mix it with urine instead.

Biochar is a tricky one. It probably comes down what scale you approach it at, and what resources you use. I like the waste from agriculture angle, for example charring waste husks. I am going to try bramble next, a ‘waste’ we have plenty off. You could of course argue that the brambleshould be able to rot down and contribute to soil matter. However, you are then losing lots of CO2 to atmosphere. Its all about balance isn’t it.

I love this subject matter and am happy to have a debate at any time. I’m still not sure myself, but I’ve got lots of thoughts on the subject.

More reading:

Swansea university have well constructed thoughts and research on biochar

There are a few books on the market:
The Biochar Solution: Carbon Farming and Climate Change (2010), by Albert

THE BIOCHAR DEBATE (2009), Schumacher Briefing No.16, by James Bruges

Biochar for Environmental Management, Science and Technology (2009)
Edited By Johannes Lehmann and Stephen Joseph
(expensive but worth it for a comprehensive if not already out of date introduction)

Look at what James Lovelock thinks (hmm)
“There is one way we could save ourselves [from global heating and that is through the massive burial of charcoal. It would mean farmers turning all their agricultural waste – which contains carbon that plants have spent the summer sequestering – into non-biodegradable charcoal and burying it in the soil … this scheme would need no subsidy: the farmer would make a profit.” James Lovelock

More about the woodland at CAT and how we manage it

Our 15 acre woodland, Coed Gwern, is a working example of an ex-plantation woodland that is being given a rest. In fact most of our firewood and coppice products come from our on-site woodland and garden trees. Coed Gwern has very good natural regeneration, and has required very little replanting. I named the woodland Coed Gwern because I believe, before it was drained, it was a wet woodland with alder (gwern in Welsh). It is my hope that we can help this patch of woodland become a rich and diverse ecosystem. Because of its young age, the woodland is always evolving. It is a pleasure to watch it and encourage greater complexity within its ecosystems. Coed Gwern aims to be a social, economical and environmentally sustainable woodland. We teach this philosophy through a range of courses and educational day visits, and also through local “knowledge shares”. Our next course is actually this coming weekend: Practical Woodland Management . Bob Shaw, a woodsman from Aberystwyth and a great inspiration to me, will be the lead tutor. Also, we are lucky to have a local horse-logger and CAT employee, Babara Hadrill, to do a demonstration of low carbon timber extraction. If you haven’t managed to book on there are plenty more courses, but to give you a helping hand you can refer to the Small Woods Association or Coed Lleol. The Small Woods Association have provided an excellent resource for preparing a management plan for small woodland sites.

An axe to grind

by Grace Crabb Biology Department

grace_nologoI have been grappling with my gas-guzzling chainsaw use for a few years now, and have taken to swinging an axe over revving a chainsaw more and more. If the Timber Jills of the second world war could do it, surely so can I (check out Timber Jills in the Dyfi forest). Axes makes less noise, you can hear and see what you are doing without the racket of the chainsaw, carbon emissions are miniscule, you can walk easily without the great weight of chainsaw boots and padded trousers and other species are happy to share your space. However, and of course, herein lies the dilemma, it is slower work and requires more “man” power. Well, I sit on the fence. My desire is to manage the CAT woodlands in the most sustainable and practical way possible. Most of the time, the volunteers and I can work together with hand tools and get the job done efficiently. However, with the bigger trees I will continue to use the chainsaw, but will keep up my axe practise. When you weigh up the carbon footprint, generating our own materials and fuel from on-site trees managed for the benefit of biodiversity has to be more efficient than buying in. I’ll get back to you with the numbers, or you can consult our own pHD student and MSc lecturer David Hood who is specialising in working this stuff out.

Our Biology Department volunteer

by Grace Crabb Biology Department
Back at CAT, our department is lucky to have a volunteer called Lou, who has recently finished an apprenticeship at Coppice Wood College in Cardigan. This centre teaches the absolute opposite to the large scale forestry practises; the art of small woodland management, where no petrochemicals are used . Lou is wonder-woman with an axe and crosscut saw. What a different experience! Coppicewood College is an inspiration for those looking to learn traditional crafts and rural practises with integrity.

If you’re interested in volunteering in the biology please have a look at the volunteering section of the website and get in touch with us.