Tools Of The Landscaping Art

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Roto Tillers January 8, 2010

Filed under: Machines - Other Uses — stevesned @ 6:35 pm

Rototillers are interesting implements. Like just about any other tool, they often reveal themselves to help in many ways which were not necessarily in their original prospectus. I’ve used them to loosen packed gravel, for example, for applying base material to the sub bases of patios and driveways. But generally speaking, rototillers are the “tractors” of the landscaping art. They fulfill the function of not only loosening soil, but of combining amendments together in specific gardens and underneath lawns. Of all the features one can picture a rototilller offering, these two stand out.

Now, not all rototillers are the same. For soils which are already loose – maybe sandy at their base or loam-rich and merely needing some mixing, the front-tined tillers such as the one pictured below might be best.

These guys have a tendency to do some serious bouncing around, however, in more seriously dense and harder-packed soils. Especially if one is opening soil for the first time, hoping to loosen it and thence to amend later, this tiller might do the trick but it is often at the expense of some very serious bouncing around and maneuvering. These are perfect for “medium” soils, with a touch of clay content. They – like almost all tillers, have a depth setting, subject to adjustment with a bar that sticks into the ground behind the business end. They are heavy but they are nice and wide and, in the right circumstances, these original tillers – design-wise – have much to offer.

Now the monster pictured above costs about 8 times more than the other two pictured. This one can cut through just about anything. Self-propelled and extremely weighty, this is pretty much the state of the Gargantuan Roto Tiller art. This one can take down a small mountain. These cut through the toughest soils and do plenty of hard work. Wrestling them can sometimes be a chore – rocks and roots can destroy a guy’s arms as they get caught up in the tines and toss you forward. In fact, it is a literal hazard, owing to the sheer power of these units. Like all bigger machinery, they require alertness and lots of getting used to.

Now we come to the junior sets of roto tillers – items which were not even on the horizon 15 years ago. The “Mantis” – so named, much like the generic “Bobcat”, owing to its initial providers.

Now, these guys are relatively tiny. The one pictured here weighs about 20 pounds and is actually one of the larger versions. These little machines have gone through quite a few adaptations. Their primary downside has always been the integrity of the metals comprising the tines themselves. Easily bendable originally, they would get so out of shape as to render the machine useless unless used in the most delicate of soils. Now, however, they have evolved a bit and have a far more durable tine. These things a truly perfect for working a home garden. I confess to having used them brutally for years myself in preparing beds in tight locations. Easily stored, one man operable and packable, they have much to recommend them. They also do an awful lot of work, let me add. I have a real “thing” for them.


The Plate Compactor December 9, 2009

Filed under: Machines - Other Uses — stevesned @ 8:49 pm

During the course of installing “hardscape” surfaces in landscapes, there are very primary considerations to assess. Regarding such necessarily durable surfaces as driveways and, to only a minutely lesser degree, patios and walkways, considerations of their bases takes precedence over nearly all practical concerns. Absolutely no surface will last without a truly “proper” base. The most important considerations are – as usual – right at the very bottom. The condition and the compactability of the soils under the base gravel and the paving above are hugely important.

(click all images to enlarge)

Most clayish subsurfaces meet a general standard of this compactability. Obviously, rocky and even sandy soils can also meet this level, provided they, too, are actually compacted. Generally, soils with large amounts of organic materials subject to breaking down and disappearing over their well-understood bacteriological life spans will effect a surface above by changing the structure and the shape of the ground below. When this happens, we get “heaving” – from either cold temperatures or from the natural disappearance and change of structure from “mass to gas”, as it were.

Therefore, there needs to be a permanent layer of permeable-yet stable gravel base under whatever surface may be provided. The thickness of this layer is the only variable factor in the mentioning of the above conditions. On patios we often go for about 4 inches of base material over a relatively compact base. That is what we are doing with our other favorite machine – the Skid Steer Loader or “Bobcat” in the scene above.

Once this surface is determined, in terms of depth, then the filling, leveling and “compacting” begins. We determine the finished grade, pull a string line and rake and try and approximate the perfect finish. At that point, we “compact” it. We use a Plate Compactor for this purpose.

We can see our hard-working little unit, shown here hiding in the upper right-hand shady spot after working hard. At this stage, with half the sub surface finished tamping, one can spot the difference between uncompacted and compacted gravel easily. These marvelous little machines have a vibrating plate carrying about 200 pounds of compacting energy and literally “walk” – owing to their ingenious shaping at the plate level – with a human guide behind them controlling turns and their direction as well. The finished product is a smooth-topped level of gravel which leaves an entire encrusted base for the work to commence on top of it. Compaction levels of 96-98% are actually possible with these machines, given ideal conditions and about 8-12% water content in the base material. 98% would be more than road worthy, and certainly adequate for driveways.

This is a “just add cement-ready” finish for concrete work and perfectly ready to add the inch of sand and then pavers for paver and pre fab slab patios. These little machines are a “must-have” for landscapers and they have proven themselves time and time again as reliable little machines with actually very few possible glitches.

Below are the finished products of each of those featured. First, the lower pictures:

And from the very top picture:

Interestingly, on brick paver work, the compactor is also used to level and further compact the actual bricks into place, once situated. We toss on a thin sheen of sand over which the compactor travels, sliding across the surface better and sinking the sand into the minute cracks betwen the bricks. As well it serves to pound it all down for a final time, incidentally raising the level of sheer compaction another percentage point.