Native plants originated in a territory. or reached it from the area they first came from without human intervention. An example of a native species is the Holm oak, Quercus ilex L. And in Lagartera in particular, the holm oak of the southern plateau, Quercus ilex subspecies rotundifolia L., forms the holm oak groves here. Now it stands out because of its fruits.
The holm oak is a very hardy tree: it withstands extreme heat and drought. Its fruits, or acorns, are used to feed livestock.
Its wood is used to make the best charcoal. In Lagartera, holm oaks are associated with thyme, lavender and broom.
A holm oak grove is the best refuge for Mediterranean fauna, and also provides shade for livestock.
Native plants are interesting because they need little care, only respect and sometimes protection. That’s why planting indigenous species when possible is the best way to tackle global warming. Holm oaks can be planted as acorns in 40x40x40cm holes (sowing the largest acorns), or as plants in forestry containers which can be purchased from nurseries.
Native species create much more complex ecosystems than those that can be seen with the naked eye. They have associated insects and other fauna, which in addition to controlling their growth so that they don’t become weeds, act as pollinators for their reproduction.
What are weeds? For some people they are the plants that we don’t want in our gardens, or in a planted area, but in the countryside, it’s useful to keep a few bramble refuges for wildlife. We also value many wild plants such as thyme and lavender. The big problem is when there is a thicket of dead, dry, extremely combustible vegetation in the months when fires are common here, especially in August and September. Then, dry thistles, esparto grass ((Macrochloa tenacissima L. or Stipa tenacissima L.) and dead broom can burn very easily, transmitting flames from one tree to another.
The fauna that eat thistles include rabbits, but they eat where they feel like eating, i.e. they like the most tender plants. So it helps to introduce grazing livestock at the right time, i.e. during the early growth stages of the most aggressive plants such as thistles and esparto grass, in autumn and winter. Sheep eat the thistles and esparto grass. Horses trample on the esparto grass clumps, which have shallow roots, and as they are heavier than sheep, horses can control these grasses better.
Sheep have both advantages and disadvantages when you want to clear land. They don’t touch the thyme and lavender, which can be killed by careless use of a strimmer, but they do love to eat tender holm oak saplings, and even the bark of young trees. Sheep can also damage young olive trees, if they are allowed to graze in an olive grove. It’s useful for sheep to eat the suckers of olive trees, and the small Holm oaks that compete with other trees, but we don’t want them to eat all the trees! So you need to protect young trees when sheep are allowed near them, and not let the sheep graze for so long that they leave everything bald, and start attacking the trees in earnest. It’s also better to let them graze in the autumn and winter, and in late spring, to leave time for the best-loved wild plants to flower.
It is worth fencing areas where there is tough vegetation that has to be removed (like thistles) for intensive grazing. But if there are a lot of young trees on a piece of land, or it’s difficult to supply water for livestock, or there’s a lot of tough dry grass, then using a strimmer may be the best solution. Horses, sheep and rabbits don’t want to eat the dry stalks of the esparto grass, so it is better to use selective strimming to eliminate this fire hazard. Traditionally, mowing with a scythe or clearing with a strimmer is done in May, when most of the wild plants have finished flowering and the grass is drying out. This is a good month to have almost everything cut back both to avoid fires, and the timing also allows us to conserve the species of plants that we want to protect.
There are other ways of controlling aggressive weeds, such as ploughing with mules or a tractor. Ploughing has the advantage of opening the soil to rain, and eliminates thistles and esparto grasses, but it also eliminates desirable wild plants, and can contribute to erosion. Ploughing helps the soil to accumulate water for cultivation. There’s no point in ploughing if you aren’t growing crops, unless you want to remove tougher weeds such as thistles or esparto grass, or you want to leave the land fallow to rest and replenish nutrients. Olive trees appreciate ploughing. When there is a slope, it is better to plough following the contour lines to avoid soil erosion. When there is a steep slope, it is better not to plough at all.
Herbicides kill everything and can poison wildlife. It’s best not to use them unless you need to control very resistant weeds such as Spanish couch, (Cynodon dactylon), a tough plant with deep roots that can even strangle saplings as well as weaker plants. It is sometimes called ’Bermuda grass’ in English.
If herbicides are applied on sloping land, there is more risk of erosion because herbicides kill the plants that prevent the soil from being eroded. They also kill the flowers on which bees and other pollinating insects forage. All herbicides, to a greater or lesser extent, are residual, in other words, they leave traces in the soil, even those herbicides described as non-residual, which just don’t leave so much.
There are plants that don’t present a fire hazard, although they aren’t eaten by sheep or rabbits, such as Torvisco, (Flaxed-leaved daphne, or Daphne gnidium L.)
Torvisco is a curious plant. The whole plant is poisonous, and the sheep know this somehow, so avoid it. As with Digitalis, another plant that sheep don’t eat, Torvisco has medicinal properties. In the old days, the Torvisco was used in Lagartera to remove fleas from the stables where the livestock was kept. Farmers used to take the branches and whack the ground with them. In some parts of Spain, Torvisco has also been tied to the tails of lambs to control diarrhoea.
A few years ago it was discovered that the sap of the Torvisco has antibacterial properties, and is effective against Escherichia coli. This plant should be handled with care, as it is irritant, and can cause skin blisters.
There are wild plants that make us happy because of they are beautiful, such as the Merendera (a type of mountainous autumn crocus, formerly called Merendera montana L. , today known as Colchicum montanum), a cormous plant that grows in the sandy soils of the southern part of Lagartera, above the Calvario (a hilltop with three crosses representing the crucifixion). It is in flower in September and October (photos by Lola Garrido).
After flowering, the leaves appear and they stay green until May, when the plant goes dormant and the leaves disappear. The corms of Merendera montana are not sold because these plants have a very short flowering period, which means that they tend not to be sold to gardeners, so it’s better to buy corms of other cultivated colchicum species, if you want them to plant in pots or gardens. (A corm is similar to a bulb, but you don’t see rings because corms are the base of the stem, while bulbs are leaves which are modified to store nutrients).
Learning something about the native plants we see in the countryside helps us to achieve a balance where we let desirable plants flourish, while controlling the less desirable ones, and this balance allows us to conserve our botanical heritage.
José García Moreno, October 2021
F. Cottigli, G. Loy, D. Garau, C. Floris, M. Caus, R. Pompei, L. Bonsignore, Antimicrobial of coumarins and flavonoids from the stems of Daphne gnidium L.,Phytomedicine, Volume 8, Issue 4, 2001, Pages 302-305, ISSN 0944-7113,
https://doi.org/10.1078/0944-7113-00036.https://www.sciencedirect.com/science/article/pii/S0944711304700446