What is Structural Soil and Why is it Good for Trees

What is Structural Soil Why is it good for Trees?

Why is structural soil effective?

Structural soil is a type of soil mixed with a specific type of gap-upgraded rock (typically 75mm clear). This is a very important part of the specification; the reason structural soil works well is that the gaps created by the rock are then filled with soil, enabling penetration by tree roots. This penetration allows the tree access to a larger space underground, and has the double function of preventing the tree roots from lifting up the hard surface, i.e. the sidewalk that is on top.

How does the structural soil get tested?

The testing of structural soil is essentially a three-part process. The soil must be tested separately. The rock must be tested and sourced with a specific sieve size attached to it to determine that it is in fact a clear rock and not a minus rock. With a minus rock all of which would be filled and therefore the soil would be effective.

There is also a stabilizing compound that is used with structural support to help the soil adhere to the rock. The specifications for this material would come directly from the stabilizer supplier; there are more than one of these.

Who can make structural soil?

Like any engineered soil, structured soil is a technical process which is best done by people who understand all the specific components and have all the components readily available with testing and prior knowledge. Making good structural soil to specification is an extremely important endeavour. Structural swell that is not up to specification is a very difficult situation to remediate once it’s already in the ground.

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Life Cycle of the Chafer Beetle

Life Cycle of the European Chafer Beetle

The European chafer beetle originated in continental Europe but is now an invasive species found in temperate climates in North America, where they are often called June bugs. The large grubs of the chafer feed on the roots of both wild and cultivated cool-latitude grasses, which has made them a critter-non-grata on North American lawns.

Knowing the beetle’s life cycle can help you defend your lawn against an infestation. Read on to find out more.

The chafer’s life cycle

The chafer’s life cycle is one year. The imago (adult) stage is only 1–2 weeks long, with adult beetles growing to approximately 13–14 millimetres (0.51–0.55 in) in length. The adult chafers emerge from the ground in late spring and mate in large swarms, usually on shrubs and low trees. They are most active on warm, clear nights when the temperature is over 19C (66F). The beetles come out of the ground at about 8:30 pm, mate through the night, and then return to the soil before the sun rises; they may return to the trees to mate again several times over the mating period.

Female chafer beetles lay between 20–40 eggs over their lifespan; the eggs are laid about 5–10 centimetres (2.0–3.9 in) deep in moist soil, and then take 2 weeks to hatch. The grubs hatch by late July. In frost zones, the grubs feed until November and then move deeper into the soil. In frost-free areas, however, the larva feed all winter. Intense feeding occurs from March through May. Then, in early June, the grubs move deeper again, from 5 centimetres to 25 centimetres (2.0–9.8 in), where they form earthen cells and pupate. The pre-pupal stage lasts 2–4 days and the pupal stage lasts 2 weeks. By June, the new beetles begin emerging from the ground.

Beware other critters, too

Not only do the larvae feed on roots, wreaking havoc on lawns, but they attract local fauna like crows, foxes, and raccoons, who dig up the grass in search of the grubs. So, in addition to root damage, homeowners also have to worry about destruction caused by larger creatures.

Why is it important to know about the life cycle of the Chafer beetle?

Knowing the life cycle of the Chafer Beetle helps illustrate is when the beetle is most susceptible to treatment which will help exterminate the pest. The beetle’s most susceptible time is when it is the egg form in late July. Although treatment can help in early times in the season, July is the most optimal time to apply your treatment. It’s also important to note that treatment should not be a one time thing.

In order to ensure the treatment and the extemination of the beetle, it is recommended to apply multiple treatments to your lawn or garden.

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Check out the infographic here

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LIFE CYCLE OF THE CHAFER BEETLE INFO

Celebrating a Legendary Landscape Architect

Cornelia Hahn Oberlander: Recipient of CSLA’s Highest Honour Here at Denbow, we are inspired by exceptional landscape architects, particularly those doing high-quality, innovative work here in Canada. As such, we were excited to hear that Cornelia Hahn Oberlander was recently awarded the Governor General’s Medal by the Canadian Society of Landscape Architects (CSLA).   In […]