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Creating Tiny Forests Using the Miyawaki Method

2022-08-16T09:15:00+00:00

The World Needs Forests

Forests are important. They are home to 80% of the globe’s wildlife population, they reduce soil erosion, lessen the impact of floods, and they remove incredible amounts of carbon-dioxide from our atmosphere, ensuring we have breathable air. The tropical forests alone store around 250 billion tons of carbon. Without forests cleaning our air, life on Earth couldn’t continue – at least not for us – but we continue to lose our forests at a concerning rate. Between 1990 and 2015, we lost 129 million hectares of forest (nearly 500,000 square miles). While deforestation has slowed, we are far from reaching a balanced, sustainable relationship with our forests. Our forests – and us in turn – will only survive if we deploy all available means to reduce deforestation and support new growth.

Afforestation – planting forests upon land previously unforested – can be a massive undertaking, but it’s one of the few things communities can do to soften the blow of global deforestation. Thanks to the late Akira Miyawaki, Japanese botanist and specialist in natural vegetation restoration, a method for afforestation has been developed that allows for small-scale, rapid forestation. This method is now commonly known as the Miyawaki Method.

The Miyawaki Method

The Miyawaki Method was developed to support the rapid growth of diverse native plant species in relatively small spaces with minimal maintenance. The method only requires a minimum space of 1000 square feet, grows ten times faster than naturally-growing forests, and the planted forest can survive nearly maintenance-free after only three years of growth. The rapid growth of Miyawaki forests is attributed to the densely-packed planting and the use of native plant species. Native species are, of course, going to be the best candidates to thrive in the selected planting location, because they’ve evolved over the course of centuries to do just that. A biodiverse selection of plants also lends itself to the long-term stability of the forest – diversity creates a layered canopy and ecological resilience. Then, being packed closely together, they’re forced into a highly competitive race to soak up the sunlight, resulting in rapid growth. After 20-30 years, the surviving plants and trees will reach heights that would have taken 150-200 years to reach in a natural process.

The resulting tiny forest is also densely-packed with benefits. In addition to supporting local biodiversity and the benefits that always come with new trees, Miyawaki forests are also 30 times better at dust and noise reduction and absorb up to 30 times more carbon-dioxide than monoculture planting projects.

Because the Miyawaki method can be applied in areas with limited land and resources while still resulting in a flourishing forest, it’s perfect for urban settings. A small parcel of land, whether it’s an empty lot or a small portion of a public park, can easily be turned into an urban forest. Urban forests are essential in mitigating the effects of climate change – both locally and globally. Our efforts on the local-scale to rehabilitate and create new forests is an important contribution to the global concerted effort to ensure a livable planet for future generations. With critical deadlines for meaningful climate action approaching quickly, we need to act quickly. Thanks to Akira Miyawaki, we have one more tool at our disposal to make swift, meaningful change.

Forget the Grass, Trees Need Your Help

2022-08-02T09:15:00+00:00

A perfectly green lawn, a long-time indicator of a functioning household and a long-time indicator of wasted resources. The Western fascination with grass lawns goes way back, originating in the gardens of the 18th century English and French upper-class. Drawing inspiration from launds – grassy clearings among trees - in the surrounding European forests, the wealthy sought to recreate the experience in their expansive gardens, leading to what we now recognize as lawns. Lawns eventually made their way to the Americas in the 19th century through our own historical elites – like Thomas Jefferson, an avid horticulturalist. Although home gardens in the US remained dedicated to consumable vegetation for several decades, by the mid-19th century, focus shifted to the ornamental. After the Centennial Exhibition in Philadelphia in 1876, where the USDA presented a how-to exhibit on growing your own grass lawn, interest steadily grew throughout the next 100 years. After several innovations made in lawncare in the early 1900s, grass lawns became a standard in the booming American suburbs. Now, another 100 years later, lawns are still as commonplace as ever, but do we have the means to keep this tradition alive?

In short, yes, we do. Despite the megadrought and surging heatwaves, our lawns can survive, because they’re well-propagated for hardship. Of all the plants in our garden, grass is sure to be the one that needs the least amount of water to survive. Although it might brown, it’s still alive and the green will return next year. This browning is part of grass’s seasonal cycle. Like other perennials, grass enters a period of dormancy once it undergoes the stresses of their disfavored seasons. This stage in its annual cycle can be delayed with extensive watering, but our limited resources would be best spent on plants in the garden that need it more.

Trees need our help most. Arguably the most valuable plants in our gardens because of the benefits they provide for our homes and communities, trees should be our top watering priority. While grasses only need half an inch (~1 quart) of water every 2-4 weeks to survive the season, trees require 5-50 gallons of water a week (or more, if the tree is especially large). As sturdy as they appear to be, trees are far more delicate than grass and they need our help to survive the ongoing megadrought, which is predicted to end in 2030 at the earliest. Paired with the fact that extended drought events are expected to become more severe and more common, our focus-shift away from grass and towards trees will likely and necessarily be permanent.

Salt Lake City’s canopy has been steadily receding since the early 2000s, largely due to trees being neglected within recurring periods of drought. Without adequate water, trees either die off or they become too brittle to withstand high winds and dense snow fall, leading to broken branches or treefall. In addition to causing damage to anything beneath them when this happens, we lose the irreplaceable benefits old-growth trees provide. Benefits like cleaner air and shade – things we’ll be immeasurably thankful for in the harsh Summers ahead, things grass can’t provide. Grass doesn’t do much for us and it doesn’t need our help, so let’s concentrate on the plants that do, trees.

Growing Trees to Shrink Salt Lake City’s Heat Islands

2023-07-13T09:15:00+00:00

In the fiery heat of Summer, shade-providing trees are a sought-after resource. They provide us with relief from the heat and they lower overall temperatures in the immediate area. While concrete, roads, and metal absorb and re-emit heat, trees provide substantial relief from the heat by both providing shade and cooling through evapotranspiration. A healthy urban forest is one of our greatest tools in reducing the heat island effect generated by our concrete jungle.

Urban heat islands are caused by a lack of cooling abiotic factors in an environment in addition to abundant human activity. Although minimally perceptible on a small scale, the heat generated by individuals driving, using machinery, or even just jogging builds up, leading to a significant heat increase in the local area. In densely populated urban areas, the heat generated by just living our day-to-day lives with the heat trapped by urban structures accumulates, creating a sweltering heat zone.

Cities overall are much hotter than surrounding rural areas, because of comparably higher levels of human activity and lower square-footage of greenspace. Within cities too, there are areas that have far fewer trees, which leads to even higher temperatures than the rest of the city. This phenomenon is immediately noticeable in Salt Lake City, where shaded areas - like Sugar House or Capitol Hill - feel notably cooler than areas with fewer trees – like Rose Park or Poplar Grove. Although the difference in temperature in these areas might only be a couple degrees, this seemingly small increase in temperature is drastic, especially when the daily temps are reaching the triple digits. With only a 2° increase, energy demands can increase up to 9%, leading to higher energy costs and more pollution.

By growing the urban forest and minimizing these barren, extreme heat zones, we all benefit. We all benefit from lowering temperatures within the cityscape, reducing energy use, and creating welcoming spaces for us all to enjoy year-round. In addition to creating an overall more inviting city for us all to enjoy, we can help protect our neighbors from heat-related illness, keep our waterways clean, and reduce pollution – all by planting more trees. With Salt Lake City’s increased efforts to plant more trees on the West Side and TreeUtah’s partnerships with community organizations in areas in need of more trees, the city’s urban forest will continue to grow and, hopefully, help our community thrive equitably.