Microforests are urban islands of coolness, they can lower the temperature by as much as 10-15 degrees Celsius! We need every kind of greenery today: those in XXL format, like large parks, and those on a medium or very small scale. It may seem that one microlas, or a few, is not much on the scale of a city, but with five hundred microlas across the country, the effect will already be felt, says Kasper Jakubowski, microlas designer.
Dr. Kasper JAKUBOWSKI - substantive director of Forest Maker, a general contractor of microlashes, an innovative method of creating groves in small spaces. Educator, landscape architect, designer of microlashes using the Miyawaki method, which was developed by Japanese botanist Akira Miyawaki. Popularizer of fourth nature, restorationist. Author of the book "Fourth Nature. Succession of function and nature of urban wasteland".
Ewa Karendys: Is microlass a forest at all?
Kasper Jakubowski: A microlass is a type of woodland, a grove, a grove in an urban space. However, it is not a forest according to the statutory definition. The idea of a microlass involves planting trees, shrubs, undergrowth and creating a forest habitat in degraded areas. In transformed areas, away from forests, we can create enclaves of forest biodiversity, which will be able to develop already without human interference.
Ewa Karendys: What else distinguishes a microforest from a forest?
Kasper Jakubowski: First of all, a smaller area - as a rule, up to 200-250 square meters, although these can also be larger developments. You could say that microlas is a buzzword, the goal is to introduce more natural, species-rich greenery to urban plots, where it is often impossible to realize something larger. Let's remember that in cities we operate not only in limited areas, but also in a maze of underground networks.
Before the planting of a micro-forest in the Wrzesnia Biodiversity Park.
© Illustrations courtesy of Forest Maker
Ewa Karendys: There are more and more ideas for greening spaces in cities: pocket parks, flower meadows, rain gardens....
Kasper Jakubowski: Microlas are a great complement to these types of solutions, while putting more emphasis on biodiversity, social engagement and education. In addition, microforests are urban islands of coolness, they can lower the temperature by up to 10-15 degrees Celsius! We need every kind of greenery today: those in XXL format, like large parks, and those on a medium or very small scale. It may seem that one micro-lot, or a few, is not much on the scale of a city, but with five hundred micro-lots across the country, the effect will already be felt.
Ewa Karendys: Just planting trees today is no longer enough?
Kasper Jakubowski:Trees have it very difficult today. We can organize actions like: a million trees for Warsaw or Poznan, but without creating the right soil conditions for trees, without proper care, they won't want to grow. They will wither within ten years, because they won't be able to withstand the climate and soil conditions we face today.
Ewa Karendys: Trees in cities are getting sicker and sicker, with stunted growth. Greenery experts are sounding the alarm that lindens, maples, sycamores and chestnut trees, and even Swedish rowans, are slowly withering away. Microlas is not affected by this problem?
Kasper Jakubowski:The key to planting a forest according to the Miyawaki method is thorough soil preparation, proper mulching. We plant forest species that have very difficult growing conditions in cities, beech, lime, oak. We do not plant foreign species. In addition, we add mycorrhizal fungi and bacteria from "old" forests during planting. At Forest Maker, we have adapted the Miyawaki method to conditions in Polish cities. We have worked out the optimal arrangement according to urban soils, which are usually very degraded. It is important to remember that we plant in post-war cities, where there is very often a lot of rubble and remnants of various networks. In fact, in many areas it is difficult to talk about soil at all - they are so heavily degraded and compacted.
Cieszyn's Independence microlasse, November 11, 2023
© Illustrations courtesy of Forest Maker
Ewa Karendys: And such preparation is enough?
Kasper Jakubowski: We feed the soil with an adequate layer of compost, often bury wood, and use other organic materials. Trees in microforests grow two-and-a-half times faster than trees planted in nurseries, that is, in forests planted without soil preparation. For the last three years, when we had floods or several months of drought, the microforests hardly needed watering. And I consider this a huge success.
As a landscape architect, I designed hundreds of replacement plantings as part of development projects. Some of them no longer exist after a few years or are in really bad shape, so I think it's no nature compensation. It's worth considering whether it's better to bet on microforest. After the first two years we see that hedgehogs, toads appear in these areas, the first birds nest. From the perspective of biodiversity in urban conditions, this is definitely a better compensation than planting solitary trees, which are simply doing badly in cities.
Ewa Karendys: Are there already examples of cooperation with developers, where instead of compensatory plantings, microforest is created?
Kasper Jakubowski: Unfortunately there aren't, because the law stands in the way. A developer can destroy beautiful tree canopies, and in their place he is supposed to plant groundcover shrubs or trees in certain perimeters. Meanwhile, a cheaper and more ecologically sound compensation would be the establishment of biocenotic zones in the form of microforests. We have other forms of cooperation with developers - the first micro-forest planted with investors in Poznan received the "Designed with humanity" award; in Cracow we have already planted five groves using the Miyawaki method.
Poznan's pocket forest on Milczanska Street in Rataje.
© Illustrations courtesy of Forest Maker
Ewa Karendys: Are microforests being created in Poland that are microforests in name only?
Kasper Jakubowski: Unfortunately, as with any good scientific method, and the Miyawaki method developed fifty years ago is such, there are some pathological realizations involved. We have signals that realizations are beginning to appear in Poland that are not done according to the method. Soil preparation is key: every inch should be properly built up and mixed. We plant thirty to forty species at the right density, and these are species from different floors of the forest. If this is poorly built, the microlasse may not perform its function, it will not be dense, multi-storied.
True microforests are very natural and biodiverse solutions - you can say that they are such small Białowieża Forests in cities. If a municipality decides to do something like this by half-measures, without proper selection of species and preparation of soil, it may turn out that in a few years there will be a big disappointment. And I wouldn't want that. In Europe alone, microgreens began to be planted about fifteen years ago, and clearly the Miyawaki method is working. This is not greenwashing.
Ewa Karendys: Can microlas be planted anywhere?
Kasper Jakubowski: The only limitation is underground networks. In Wrocław, at the intersection of Podwale and Kołłątaja Street, I designed a microlasse at the site of a former parking lot, on the ruins of a 19th-century tenement, there the soil was terribly compacted. We also designed a microlas together with the Warsaw University of Life Sciences on the campus, in a place from which we first had to remove 200 tons of rubble. There we built the soil anew. Bottom line: there are no limits, in fact we can do it anywhere.
"Little Gdynia Forest" by the Pomeranian Science and Technology Park in Gdynia, Gdynia Design Days 2024.
© Illustrations courtesy of Forest Maker
Ewa Karendys: In what locations are microforests most needed today?
Kasper Jakubowski: First of all, in new suburbs, areas with sprawling development, where we have a lot of houses and concrete, and little public greenery. Trees in micro-forests will grow two-and-a-half times faster. Other locations are the sites of logistics companies, which are just asking for the introduction of relatively maintenance-free vegetation and building biodiversity. Third: degraded areas, rubble sites, former parking lots, areas dominated by invasive species. I also see great potential next to highways and busy roads. Also near school and kindergarten areas, because microlands have an educational function. If you go to such a microforest, there are forty species of trees. Underfoot, a rich world of forest undergrowth opens up. It is even more interesting underground.
Ewa Karendys: More and more money is being allocated for greenery in city budgets. How much does it cost to plant a microforest?
Kasper Jakubowski: We have a fixed cost, it's 350 zlotys per square meter; it includes research, preparation and planting of the microlasse with residents. Is that a lot or a little? A mayor said we are cheaper than paving stones. There has been an accusation on social media that we are taking money from budgets for conservation or investment in greenery. I want to firmly say that we are not taking anything away from anyone. Very often municipalities or private companies that decide to microlas create new budget items. Today we can't think either microlas or meadow protection. We have to say: both.
Ewa Karendys: Let's assume that Kowalski wants to plant microlass on his own plot under his house. Will such an action make sense?
Kasper Jakubowski: Of course. We have such realizations in our portfolio. It happens that someone wants to dedicate a part of the garden to a natural establishment. The intentions of the clients here are very interesting. First of all, the idea of microgreens interests them, they are ready for such an experiment in their own garden. And most importantly: they want to listen to birdsong. They know that a natural, dense microforest with many species of trees will attract birds.
Planting the first Miyawaki forest on Roosevelt Island in Manhattan, New York, spring 2024.
© Illustrations provided courtesy of Forest Maker
Ewa Karendys: A blacksmith has decided to plant a microforest, what next? Does he have to put a lot of effort into taking care of it?
Kasper Jakubowski: He will have to weed and replenish the mulch for two years, because we mulch very thickly with bark, leaves, straw. It is also necessary to replenish species that may have fallen out, to bring down dead wood, which is a fantastic habitat and, by the way, acts as a sponge. In the case of implementation for companies - we train employees. It's wonderful when, after planting a micro-forest, we can come back with these employees to carry out weeding or mulch replenishment. They often rub their eyes in amazement. They planted species that were 20-60 centimeters, and later they can't find their trees and shrubs that are already 2 meters tall. An individual is able to take care of the microlas himself, I encourage such garden fitness. It's important to take a walk through the micro-forest once a month, tilt it, pull some weeds. If there is a very big drought, we can water the microlas, but we don't need a barrel for this.
Ewa Karendys: I'll admit that I was surprised to learn that microlasses grow up to twice as fast as conventionally planted trees.
Kasper Jakubowski: Indeed, an experiment from Kent County in the UK showed that after two years, microforests on properly prepared soil grow two-and-a-half times faster than forests planted conventionally using the farm forest method. Our experiments in Krakow and Września confirm these observations.
I often explain that while speed is important, these are not McDonald "s type forests. The most important thing is that they form a certain micro-ecosystem, that these species interact with each other. Someone will say: why plant micro-forests, spend money, if we can let nature on an urban plot grow on its own. For many years I dealt with the fourth nature and argued that sometimes the best we can do is not to disturb nature. However, another problem has arisen: often these urban fallow plots are overrun by invasive species such as ash-leaf maple, dogwood, American cherry or Canadian goldenrod, considered by many biologists to be a major threat. These species, brought by humans from North America or Asia, are beginning to invade the landscape and are taking space away from native species due to their strong competitiveness. They are costly to remove. We can create something very similar to these natural fallow areas, but by preparing the soil, we create a forest consisting only of native species.
Planting a microforest has an educational and integrative function for the local community
© Illustrations provided courtesy of Forest Maker
Ewa Karendys: In Japan, where the Miyawaki method originated, the attachment to trees is greater. In our country, respect for trees tends to be mixed, as evidenced by frequent mindless cutting down.
Kasper Jakubowski: In Poland, we don't have a problem with planting trees, as can be seen from hundreds of tree planting campaigns or sowing flower meadows. We have a problem with protecting old trees, they are often cut down as threatening or inadequately cared for. Once we get past the southern or western borders, such a problem no longer exists. Foresters boast that there are more trees in the forests, only that we are outnumbered by young trees, and the greatest value is in the oldest ones.
Ewa Karendys: Which realizations of microforests from Poland and the world can be considered exemplary?
Kasper Jakubowski: I think that these are the microlashes that we have established in Gdansk, Krakow, Rybnik or Lodz. We plant them identically to the world and according to the Miyawaki method, and even better, because we still introduce forest undergrowth, that is, we do something that the Dutch and the British don't do. For me, an important realization last year was the planting of a microlass on Roosevelt Island in New York. Among other things, as part of the micro-forest we realized a textile meadow, a path with a mineral surface was created, we added some small architecture, a minimum of lawn, and restored the hedge that grew there. I consider our microlands a model example of an alternative to expensive revitalization of urban plots and squares.
Interestingly, Dutch scientists who studied eleven 5- and 7-year-old microlots inventoried 636 animal species and 298 plant species in them. This research has convinced skeptics that even area-small forms of urban conservation can host numerous species of flora and fauna. And then there is the extremely important world of fungi.
Common buckthorn - one of 35 native tree and shrub species in Krakow's Zablocie micro-forest | the key to planting a forest according to the Miyawaki method is thorough soil preparation, proper mulching
© Illustrations courtesy of Forest Maker | Photo: Michal Algebra © Illustrations courtesy of Forest Maker.
Ewa Karendys: Do you believe that on a concreted square, in one of the Polish cities, sooner or later a micro-forest will be created?
Kasper Jakubowski: I believe it very much. Over the past dozen years or so, we have concreted hundreds of hectares with EU money. We have often turned the parks and meadows that exist there into biological deserts. Let's take out the paving, create soil and plant microlasses. I'll say more: we can make microforests with small retention and manage some of the water from the environment. Some local governments come to us with a proposal for a micro-forest consisting only of edible species. They are good for pollinators, and we have a huge collapse in the insect world. Introducing edible trees into cities could be a hit.
I believe we will de-conetone and introduce more natural greenery. And, importantly, that which is meant to serve nature, to retain water, to favor pollinators and birds, can be built around modern settlements. It is possible to combine both worlds. The biodiversity and climate crises we have in Poland are primarily a crisis of imagination. Some find it hard to imagine that our cities can look different, that revitalization can be part of renaturalization, that we can leave concrete only where necessary. And that investments like microlas can also be opened with pomp and a bang - politicians care about that, after all.
Ewa Karendys: Thank you for the interview.
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