I want to give two thumbs up for a useful math book for agriculture/horticulture/landscape practictioners. It is called Mathematics for the Green Industries.

The subtitle of the book is called "Essential Calculations for Horticulture and Landscape Professionals" and that is what you will find in this book. The calculations are grouped into major areas of concern such as estimating and computing landscape areas, fertilizer calculations, pesticide calculations, turfgrass calculations, irrigation calculations, greenhouse area and volume calculations, and so on. If, for example, you need to figure out how much fertilizer or soil amendment you might need for a particular landscape job, you can find some discussion to frame the problem and then solve it through a step-wise set of calculations. Or, say you want to build a green house and have to figure out how much material to buy to cover it or how much heat it might require to maintain a temperature. To figure out how much cladding material you will need you can lookup techniques for calculating the surface area of triangular or domed greenhouses.

To compute the surface area of your greenhouse you can proceed by breaking down the problem into computing 4 separate surface areas:

1. Compute the surface area of the roof (triangular or domed roof shapes).
2. Compute the surface area for the front and back wall sections that are part of the roof (e.g., the gable area).
3. Compute the surface area for the front and back walls minus the gable area (usually a simple rectangular area calculation - length x width).
4. Compute the surface area for the long walls (usually a simple rectangular area).

To get the overall surface area you simply add up all the component areas. So the book gives you ways of breaking down problems into component calculations and then bringing them all together to get the answer you are looking for.

The book does not assume too much mathematical sophistication of its readers. There is introductory material on computing the area and volume of various common shapes (e.g., squares, boxes, circles, spheres, triangles, prisms, etc...), basic geometry, and working with fractions. Working with fractions is essential because you are often converting from a quantity measured in one format (gallons/acre) where you might need it in another format (ml/cm) for the purposes of, say, adjusting a spray nozzle. The book comes with lots of appendices with useful conversion factors and equivalents.

The book is definitely useful as a reference to have around in case you have to do any green math. I think it might also be a good book to use in high school classrooms. There are many practical geometry techniques that are used creatively to solve complex practical problems that arise in green industry jobs. Some students might appreciate mathematics more when embedded in these practical problem solving contexts - especially students in rural economies who would practically benefit from such knowledge. I think it could form the core textbook for a "Green Math" cirriculum that might be supplemented with other calculations like wind turbine power and size calculations, solar efficiency calculations, hydroelectric calculations, EROI calculations and many other interesting calculations that might form part of a green math cirriculum.