Managing land and soil

Managing different soil issues

Prof. Thomas Walker of ‘Maggie’s Garden Show’ fame, and a former professor of soils at Lincoln University, often shares the advice given to him by an old English farmer during World War II.

“The secret to managing soil well is to treat it like a new-born baby. Remember to keep its:

bottom dry – use drainage carefully to prevent waterlogging
belly full – manage nutrients well
face clean – rotate grazing to manage weeds and utilise your grass well.”

Different soils in our region have different characteristics, and different management needs. Find out about different soil management needs in the Waikato region:

Cultivation

Cultivation provides us with crops and new pastures but can put a lot of pressure on soils. It can lead to a reduction in organic matter and increased erosion. Find out more about the effects of cultivation on our soils.

Nutrient management

Healthy pasture needs healthy soils, so it’s important we manage nutrients carefully. Find out about nutrient management and use our online calculation sheets to work out your nitrogen and phosphate needs for both dairy and drystock farms.

Peat soils

Peat is a highly productive growing medium. However, in order to establish productive pastures and crops, peat soils need careful drainage and cultivation. Find out more about managing peat for maximum productivity.

Pugging and compaction

In areas where high stock numbers trample on wet ground, the soil is vulnerable to pugging and compaction. Check out our tips on minimising pugging and compaction and protecting your soils.

Managing runoff on farms

Managed waterway margins and drains help prevent pollutants (such as nitrogen, sediment and faecal coliforms) from entering waterways by intercepting farm runoff. Find out more about fencing streams and rivers and fencing farm drains.

Land capability and use

What land is being used for today may be quite different from what it is capable of being used for in the long-term. It’s important to know the limitations of your land and its soil, and what uses it is capable of supporting.

Land use capability classes are one way of assessing the limitations of your land. Land is assessed according to its:

tendency to erode – for example, flat land versus steep hill country
type of soil
wetness – for example, too much or too little drainage
climate – including hours of sunshine, rain levels, wind, maximum and minimum temperatures.

There are eight land use capability classes, ranging from Class I (flat land with good soil and few limitations) to Class VIII (steep land with severe physical limitations):

Classes I to IV are suitable for cultivation.
Classes V to VII are not suitable for cultivation, but may be better suited to farming or forestry.
Class VIII is not suitable for any productive use and is best left in native bush for catchment protection.

The table below gives more detailed descriptions of the different land use capability classes. It also gives the percentage of the Waikato Region falling into each category.

Land Use Capability Class	Description	Percent of Waikato Region
I	Good multi-use land, flat to very gently sloping, deep, easily worked soil, negligible risk of erosion.	1.9
II	Flat to gently rolling land with slight physical limitations, may be used for cultivated cropping, horticulture, pastoral farming or forestry.	11.2
III	Land with moderate physical limitations for cultivation; may be used for cultivated cropping, horticulture, pastoral farming or forestry.	11
IV	Land with severe physical limitation for cultivation; constraints on the choice of crops able to be grown; may require intensive soil and water conservation treatment and careful management practices.	14.1
V	Too many limitations to be cultivated for cropping. Negligible to slight erosion risk under pastoral or forestry use. Typically stony, wet or sloping land with high quality, stable soils. Where slopes prevent cultivation some horticulture may be suitable.	0.4
VI	Moderate limitations for pastoral use. Suitable for forestry.	36.7
VII	Severe limitations for pastoral use. Suitable for forestry.	15.9
VIII	Severe physical limitations; not suitable for any form of cropping, pastoral or production forestry use; only suitable for watershed protection.	5.3
Other	Includes lakes, quarries, and towns.	3.5

Get to know your soils

Soils aren’t created equal. When managing soils for pastoral farming, it’s helpful to think about:

the strengths and weaknesses of your soils
whether your soils are prone to pugging in the winter
whether your soils are prone to drying out in summer.

To learn more about your soils, consider mapping them. Try keeping records about how your soils and pastures cope with wet and dry extremes over time.

Threats to our soils

In the Waikato region, two thirds of our soils need special management to maintain their quality and stability. How we manage our land and soil is a critical issue for long-term sustainability.

There are four main threats to land and soil in the Waikato region:

erosion – the loss of soil from land
pugging and compaction – damaging the soil structure and its ability to support life
contamination – from excessive nutrients or chemicals not normally present
loss of organic matter and nutrients – for example, leaching of nutrients.

How susceptible a soil is to these threats influences what land uses it is suitable for.