The low-down on roots
At Long Beach Plumbing, we spend a lot of time talking about tree roots. Adventitious roots, contractile roots, structural roots − you name a type of root and we’ve got something to say about it.
That’s because roots are the most common cause of pipe blockages; something else we know a fair bit about. The potential of tree roots to inhibit flow within your pipes, create blockages and damage can’t be underestimated.
Roots do have a vital role to play in your garden, of course. Without roots, there would be no foliage as roots provide your plants with a secure supply of nutrients and water as well as anchorage and support.
We thought you might be interested in knowing a little bit more about these amazingly clever, yet potentially destructive, organisms.
Root architecture
The pattern of development of a root system is termed root architecture. The architecture of a root system can be considered in a similar way to above-ground architecture of a plant in terms of the size, branching and distribution of the component parts.
There are two types of roots which are commonly found in suburban gardens around Melbourne: fine roots and coarse roots.
Fine root are primary roots (usually less than 2 mm diameter) that have the function of water and nutrient uptake. They are often heavily branched and support fungi. These roots may be short lived, but are replaced by the plant in an ongoing process of root ‘turnover’.
Coarse roots are roots that have undergone secondary thickening and have a woody structure. These roots have some ability to absorb water and nutrients, but their main function is transport and to provide a structure to connect the smaller diameter, fine roots to the rest of the plant.
Having a balanced architecture allows fine roots to exploit soil efficiently around a plant and the plastic nature of root growth allows the plant to then concentrate its resources where nutrients and water are more easily available. A balanced coarse root architecture, with roots distributed relatively evenly around the stem base, is necessary to provide support to larger plants and trees.
Tree roots normally grow outward to about three times the branch spread. Roots on one side of a tree normally supply the foliage on that same side of the tree. Thus when roots on one side of a tree are injured, the branches and leaves on that same side of the tree may die or wilt.
Root depths
The distribution of vascular plant roots within soil depends on plant form, the spatial and temporal availability of water and nutrients, and the physical properties of the soil. The deepest roots are generally found in deserts and temperate coniferous forests; the shallowest in tundra, boreal forest and temperate grasslands.
Some roots can grow as deep as the tree is high but the majority of roots from most plants are found relatively close to the surface where nutrient availability and aeration are more favourable for growth. Rooting depth may be physically restricted by rock or compacted soil close below the surface, or by sewer pipes.