Topsoil

Technically IÂm unsure that loam is just topsoil, but the dear doctor might be right. Topsoil is usually defined as the top few inches of soil that most crops are grown in. Loam is usually measured in feet.

I live on Norge silt loam. ItÂs defined as a surface layer of brown silt loam about ½" thick. The subsoil is reddish brown silty clay loam to a depth of about 36", red silty loam to a depth of about 58", and red silty clay to a depth of 84". I bore you with this verbiage from my Soil Survey manual to show the varying degrees of loam you find as you go straight down.

In the county where I live the USDA Soil Conservation Service lists 98 different soils. They are different based on elevation, grade of slope, vegetation, and the amount and percentage of cay, silt, or sand loam and each one of those soils change as you dig down.

Having said all of that, I donÂt use loam, have never used loam, and will never use loam. I prefer a large percentage of high fired clay particles called haydite mixed with a fine pine bark soil conditioner with a little 702 Metro Mix thrown in just to say I threw it in.

Most people I know prefer a soil-less fast draining mix.

If you get 100 people to tell you what they use, youÂll get 100 different answers.

randy

What we in the US commonly refer to as loam, is considered by most to be inappropriate in bonsai soils. As the term "loam" relates to bonsai, it depends on what book you're reading and how old the book is, but you'll most commonly find it listed as a soil component in books by Japanese authors. They are not referring to our loam, but a soil, volcanic in origin, with fairly large particles that comes in colors. I've seen red and black loam listed as a soil component in books, but there are brown and yellow loams, too.

During volcanic eruptions, powder-like dust and small particles are spewed out in huge quantities. As the deposits are washed by rain or moving water, the fines are carried away, and what is referred to as "loam" remains.

Al

Forget trying to use "loam" in bonsai soil.It is not even stadardized in nurseries, so what you might get one place might be useable, but obtained elsewhere could wind up contributing to the death of your tree.

The definition of "loam" is so loose as to be useless. It's not used in bonsai soils much nowadays anyway. Do a search on "bonsai soil" here to see what is used.

Loam is a DIRT its fluffy and light it has good drainage. Now about making your own Heres what I've used for about 30 years now
1/3 sifted crushed lava or brick, sifted through a 1/8" and a 1/4" hardware cloth home made sifter. use the 1/8" for small trees and the 1/4" for larger ones. Now sift some miricale grow potting soil remove the peralite by placing the sifted mix in a bucket half full add water and hand mix the perolite will float to thr surface and can be poured off or use a piece of screen to scim it, dry in the sun , again use the 1/4" and 1/8" inch sifters. use the stone that dosn't pass through the 1/4" for the bottom of you big pots. Add 1/3 of this mixture to 1/3 leaf mold-compost. of chopped peat moss now wash the brick -lava to get rid of the dust. Sun dry the stone and mix all componants well. Mix well drain fast but retain enought water and air to promate fast root growth. The crused sharp edged stone will cause the new roots to split and multaply faster than small pea stone. a mix of 1/4 peat moss and 3/4 brick is a great cutting starting mix when placed in standing water(remove excess every 3 days to keep the skeeters down.

Loam is defined often by locations as you have discovered, when I was first starting out I discovered that it refered to the kind of material you found on the floor of a hardwood forest, a great percentage made up of leaf mold. So---forget about loam. You are going to have to make your own soil. Start with three components, composted pine bark mulch available at most garden centers, coarse sand found a store dealing with swimming pool supplies and sold for pool filters, and calcined clay or small red volcanic gravel if you can find it. Mix together all of the above in equal amounts by volum for a basic pine/conifer mix. If you are growing Maples and othe decideous trees add more pine bark mulch. All of these items are designed to hold there structure over time, they are slow to break down and slow the drainage. A rapidly draining mix is what you are looking for.

Vance Wood.

good idea for soil mix