Rooting depth?

[SilliamWhale]

do you think rooting depth actually makes a difference to yield?

I'm inclined to think its not important as some think - even for oilseed rape.

I'll explain:

In No Till it is sometimes likely that roots will not grow vertically as in a tilled soil, but I personally don't think it will lead to any damage or lack of vigour. Indeed given that we apply most of our fertilisers to the surface anyway (and they can only go down can't they?) then do you envisage a problem?

 

[Simon C]

I would have thought shallower the better providing the seed is into moisture and is covered up properly and out of the way of slugs. The shorter the time the shoot takes to emerge and start photosynthesizing, the more vigour it will have. I have seen very deep drilled wheat, 3 inches or more, becoming long and leggy and reluctant to tiller. I much prefer a stubby plant with tillers growing sideways, fat on the ground over winter.

 

[BSH]

I would have thought that as moisture is a huge limiting factor that root depth was important? Whilst many of the nutrients maw be close to the surface the moisture (in a dry year or one of the extended dry springs we have had) will be lower. it is certainly a big factor in grasses and legumes.

 

[155tm]

In a dry year or times of moisture shortage (whatever that is) a deeper crop should continue to find moisture and continue to grow, where a shallow rooted crop should suffer a degree of stress.

 

[Desangosse Ltd]

Agree 155tm, also we need to look at "crown" size.......lodging etc

 

[Will Blackburn]

In the DD situation I can see Will has a valid point. A great play is made in "ploughmans folly" of cultivation shearing natural capillaries so moisture cannot make its own way up.

 

[Elmsted]

I would have thought that as moisture is a huge limiting factor that root depth was important? Whilst many of the nutrients maw be close to the surface the moisture (in a dry year or one of the extended dry springs we have had) will be lower. it is certainly a big factor in grasses and legumes.

74 0r 76 can't eactly remember we as usual had lucerne for silage in a tower. The drought was such that on the light chalk soils near cliffs of Dover. It was about all that was green. Fed ours and a neighbours cows. Roots down around 20 ft.

But same year wheat yeilds where pretty good too. Roots pretty shallow in those days about a metre. However one metre cubic of soil has often 1000 km's of roots. Totaly different to tap roots.

 

[JD-Kid]

it's an odd one in some cases shallow roots in a light rain will get up and gong faster after the dry were tap roots tend to need more to get going again

if it is damp most of the time i don't belive it makes a huge diffrence but dryer deeper roots will be better

dose it need to be beaten to a pulp for the roots to get down i don't think so but there would be a need for some form of looseing both for roots to get down ,and water to fill a larger area

 

[Elmsted]

it's an odd one in some cases shallow roots in a light rain will get up and gong faster after the dry were tap roots tend to need more to get going again

if it is damp most of the time i don't belive it makes a huge diffrence but dryer deeper roots will be better

dose it need to be beaten to a pulp for the roots to get down i don't think so but there would be a need for some form of looseing both for roots to get down ,and water to fill a larger area

Lucerne which you grow on the cliff side of south Island are I reckon same as English or central east Europe lucerne. Grow with the ability to hammer through even concrete. Crikey there is here a huge amount grown lots in p******lts hard and compacted to hell, next door to 20+ years of continous Maize same solid layer at 8" both consistently produce year in year out some years better than others.

 

[JD-Kid]

yea mainly a winter dormant type a few 6's and 7's kicking around but not that common .. it will punch down if it can get a crack and soil mins suit it have seen it only go 6-8 inchs and stop think it's the frist 2-3 years if it can get going it's able to get down but any thing damageing the tap root in the frist year it's hard work for it