Ditch Irrigation Questions

[SnareBear]

I have four Rai of farm land that I will plant around 80 fruit trees on. The land is a slight slope with the local irrigation canal (dam supported) coming in at the high ground corner. Nearby that corner is the lowest ground, where I have dug a 600 m2, 3m deep pond.

My plan is to have the canal supply water for the trees through irrigation ditches, but also have it run in a waterfall into the dam where I will have fish. This seems like the simplest and cheapest option for irrigation.

The dam will also be a backup for the dry season so I can support the trees with water by pumping it up to the canal entrance where it runs into the ditches. The dam currently has some water, so it reaches the local water table for sure, but I have yet to find out how much I can pump out per day.

It would be very nice with some hints on how to plan the orchard and ditches. I guess the simple approach would be to plant the trees in rows 6 - 10m apart and then have the ditches run between each row. I can see how that would work for mature trees with a wide root system, but how would it work for young plants? Can ditch irrigation be used right from the start, or is manual watering a must in the beginning? I guess I could make small T-intersections at each plant leading the water closer, or maybe dig a small "pond" right next to each plant so more water is soaked into the ground. What is the common practise for this?

Thanks for any hints.

Edited May 1, 2010 by SnareBear

[slapout]

Ditch irrigation works after the trees get a good lateral root system established (5 to 6 year.) or more/less depending on the tree your planting. For 80 tree, probably the easiest and most economical way is a irrigation canal down the middle of the tree rows and use the Thai bucket method to water trees individually, when tree drip line reaches the hand dug canals you can water via them 100%. Otherwise plastic pipe with a open T spaced at each tree, If water source is higher than land this system could work via large pipe at water source, reduced down , with valves installed, and gravity dependent. It all depends on how labor intensive is acceptable, and the money you want to invest.