Having dug our holes the week before it was now the time for the archaeologists to dig theirs in the more sensitive areas. Oh boy, did they have their work cut out for them?! The weather was rather inclement and the holes were filling up with water faster than they could dig. As it turns out there were hardly any archaeological features to speak of except for some demolition debris, an old red brick culvert from the 18th century (still working) and, best of all, they dug up a Burwell /clunch stone pile which was probably a wall associated with the apparent house platform. We were not going to plant a tree in this hole but would plant it some five yards away so as to avoid disturbing the house platform as the tree gets older. Between us and the archaeologists we hardly found any medieval or post medieval pottery either. Some might say that this was disappointing but I say we achieved what we set out to achieve which was to plant the trees away from any archaeological features which are there.
Day off in lieu so what job to give Shane and Jayne to do? The Timberwolf wood chipper was still out of action because of an intermittent electrical fault (that’s now been sorted out by Sean Philips the agricultural engineer; it would seem that there is a tiny, weeny capacitor that helps energise the safety switches… hope it’s this!) Anyway, it was cold and dreary but aha! The burning bin was available and a fire would be most welcome. It’s quite surprising how quickly the brash burns in the fire bin- so fast that it may even be quicker than chipping the brash. At the end of the week John and Sarah also kept themselves warm for the day as well as taking delivery of the first batch of trees for the parkland planting this year. Didn’t heel them in (put them temporarily in the soil by digging a trench and covering the roots), just kept them in the black bags because they were going to be planted on Sunday and Monday.
So, on Sunday, the Cambridge National Trust Volunteers arrived to help plant the parkland trees. The day went well and fairy dust ( a mycorrhizal mixture) was added to the soil. Below is a piece nabbed from the web: ‘Trees for life’ ‘Mycorrhizas
Fungi are a cornerstone of woodland ecosystems. Yet they are often overlooked, as so much fungal activity carries on unseen beneath the surface of the forest floor. Even the more conspicuous fruiting bodies, mushrooms and toadstools, represent only a tiny glimpse of the main body of the fungus. There is a vast network called the mycelium, made up of fungal threads (hyphae) carrying out their essential work in wood and soil. Yet the lives of plants, those more obvious members of the woodland community, are intimately bound up with, and dependent on, those of fungi.
Mycorrhizal partnerships are symbiotic, or mutually beneficial, relationships between plants and fungi, which take place around the plant’s roots. While there are many species of fungus which do not form these partnerships, the vast majority of land plants have mycorrhizas (from the Greek mykes: fungus and rhiza: root), and many plants could not survive without them. Fossil records show that roots evolved alongside fungal partners and that fungi may have been crucial in helping plants evolve to colonise the land, hundreds of millions of years ago. Broadly speaking, there are two main kinds of mycorrhiza: Arbuscular mycorrhizas penetrate the cells of their host’s roots, and most plants develop this type. Ectomycorrhizas surround the roots without penetrating them. Trees may form either type, and some form both. In each case there is cell-to-cell contact between the plant and the fungus, allowing nutrient transfer to take place.
Benefits to the fungal partner
The fungus within a mycorrhiza receives sugars from its plant host. Since fungi do not photosynthesise (produce their own energy from the sun) and most plants do, the plant becomes a vital source of energy for the fungus. Certain mycorrhizas will actually live inside the plant’s root, so the plant can also help isolate them from competitors.
Benefits to the plant
Fungi transfer essential minerals such as nitrogen and phosphorus from decaying organic matter to the plant. They are able to use chemicals (enzymes) to break down substances which plants cannot use unaided, such as cellulose, thus making more nutrients available to the plant. The countless hyphae extending from the plant’s roots also increase the overall area of nutrient and water uptake. These fungal threads can be very fine, branching between soil particles, and even exploring the shells of dead insects! Some mycorrhizas may speed plant growth, stimulate fine root development and lengthen the life of the roots. They can also protect plants from drought, predators (such as nematode worms), and pathogens (micro-organisms that cause disease). Furthermore, in areas polluted by toxic heavy metals, fungi can buffer their plant partners against harm. A diversity of fungi is valuable, as different fungi will specialise in the various functions mentioned above, so one species may be good at taking up particular nutrients, while another will be better at producing enzymes.
Mycorrhizas in forest ecosystems
To give an idea of the scale on which mycorrhizal partnerships take place, research in Swedish boreal forests found that between 60,000 and 1.2 million ectomycorrhizas were present in one square metre of forest! In old forests, individual fungi can be particularly large – the mycelia of some extend over 100 square metres. The effects of mycorrhizas are not limited to the fungus and its host. One of the many ways in which they maintain the health of the soil is by acting as a ‘safety net’, preventing nutrients from being leached away. The overall ecosystem can benefit from higher plant diversity and improved soil structure. Research in temperate forests in the Pacific Northwest of North America has revealed that the networks of mycorrhizas in the forest allow the transfer of significant amounts of carbon between trees, even those of different species. Carbon is the ‘energy currency’ within ecosystems, and it was discovered that when Douglas fir (Pseudotsuga menziesii) was shaded, there was an increase in the amount of carbon it received from birch (Betula spp.). This insight calls for a shift from the emphasis on competition to one on resource distribution in plant communities, and illustrates how mycorrhizas can promote coexistence and biodiversity.
Moreover, while the trees in forests are recognised as an important carbon sink, the fact that mycorrhizas also store large amounts of carbon means that they may have a crucial role to play in dealing with global warming. Some examples: Investigations into mycorrhizas really began in the 1880s with studies to promote truffle production. While these highly prized edible fungi are not a feature of the Caledonian Forest, there are a number of well-known mycorrhizal fungi that are. The chanterelle (Cantharellus cibarius) is a delicious, orange-yellow, almost trumpet-shaped mushroom, with a pleasant smell of apricots. It is found in many kinds of woodland, including pinewoods. The cep or penny bun (Boletus edulis) tends to associate with oak, and is also a delicacy. Among the poisonous fungi is the fly agaric (Amanita muscaria), which forms mycorrhizal partnerships with birch. This is the familiar toadstool of storybooks, with its vivid red cap and white spots. Although potentially lethal, it is also known for its psychoactive properties and these were apparently utilised by European witches and Siberian shamans.
Less well-known, and often quite rare, are a group called the tooth, or hedgehog fungi, so named because of the spine-like bristles on the undersides of their caps. A number of these, such as the greenfoot tooth fungus (Sarcodon glaucopus) associate with Scots pine. Tooth fungi in the Caledonian Forest are often found growing on bare ground, such as eroded river gravels, and possibly play a role in assisting trees to colonise these areas. Like many woodland fungi, some of the soft-bodied tooth fungi provide food for a range of invertebrates and small mammals. Interestingly, the fruiting bodies of ectomycorrhizal fungi are rarely found growing directly beneath their host tree, (although they may still be beneath a tree of the same species) This shows that tree root systems can be surprisingly large.
Threats to mycorrhizas
Mycorrhizas can be damaged by soil compaction and disturbance, as well as by the use of certain chemicals, all of which occur in intensive agriculture and forestry. Applying large amounts of inorganic fertilisers to young trees, can suppress the development of mycorrhizas. Excess nitrogen, whether from fertiliser use or atmospheric pollution, chiefly affects the reproductive parts of the fungus, and so could have long term effects on fungal populations.
Mycorrhizas in woodland conservation and restoration Many foresters and farmers are developing an awareness of the importance of looking after mycorrhizas, and the soil generally. Organic methods, and low impact forestry techniques, such as the use of horses for small-scale timber extraction, all help to maintain the integrity of the soil. Mycorrhizas are so crucial to tree health, that the practice of inoculating the soil with fungi at the time of planting is becoming increasingly common. Because of their ability to buffer trees from toxic minerals, inoculation is particularly useful in restoring vegetation to heavily contaminated land, such as former mining sites. There is no doubt that the restoration of wild, native woodland could not take place without these complex, fascinating and hidden partnerships. Dan Puplett‘
By the end of Sunday we had planted 66 trees and on Monday almost all the forestry team were in (which also helped me to have a few days off during the week as I didn’t have to organise each day). A cold and wet start soon turned into a lovely, sunny day although, as the day wore on, the weather changed back to being overcast, windy and cold again. Having planted in the drier holes on Sunday it was time to tackle the low-lying ground which, although a lot drier than last year, was still remarkably wet on top.
In fact, in some places, it was so sodden that the holes were absolutely full to the brim with water. Anyone got some swamp loving trees for sale?!!! There are a few natural springs which feed the ponds to the south east of the Hall and I suspect that’s where all the water comes from.
The only thing to be done was to bale out the holes with a bucket, plant the tree pronto and hope for the best. In the worst areas I have actually departed from the prescribed trees and planted species that are more tolerant of the wet gleyed clay soil conditions : species like black poplar and London plane as these still grow to a majestic height and form, somewhat like the elms that once grew here. We’ve planted all the trees we had so just have to order the last 30 or so still needed, get them planted and then we’ll move onto erecting the guards.