Teachers tips 7: Know your plants

Back to Te Māra a Tāne

New Zealand has many plants; in fact there are more than 4,500 different trees and shrubs not counting some 1,200 other plants such as the ferns and mosses. Each one has a different part to play in its habitat and so if we are to tell one from the others each plant must have a name.

Identifying a particular plant is the first step to understanding the complex relationships which exist between plants of the same type, different plants and animals and the environment in its natural habitat.  Luckily for TfS students (and their teachers!) only a few botanists need to name more than a couple of hundred plants.

It is not unreasonable then to expect a TfS student to be able to name at least half a dozen plants. As TfS is involved in bush restoration planting a good place to start is that students should be able to identify manuka and kanuka, flax and cabbage tree, karamu and karo, totara and kahikatea and mahoe and mapou; and for dune restoration be able to tell the difference between pingao and spinifex. (Follow the links for information about each plant).

Enthusiastic students may even be able to identify all 38 of the plants listed on the TfS website

Becoming familiar with some of New Zealand’s native plants provides many opportunities for student activities. Here are just a few:

Adopt a plant
Students in your class can choose a plant from the list above and make a presentation (verbal or hard copy) on what they have found out.

They can start by using the TfS website as a resource but encourage a visit to a library or other websites. They should, for example, be able to record its common, maori and scientific name, describe the leaves, flowers and fruit, the plant’s size and shape, its relationship with other plants and animals, its value in its habitat and what it can be used for.

Some children may be able to find a specimen of their plant growing nearby which they can watch over the coming seasons, recording the different stages of the plant’s life cycle and how various environmental factors affect its growth.

Plant measurements
Keen students may wish to collect some leaves from their adopted plant, outline them on some graph paper and make an estimate of their average size. They can then make an estimate of the total number of leaves on the plant (they will come up with some interesting ideas on how to do this!). Then multiply the average leaf area by the estimated total number of leaves to give an approximation of the total leaf area of the plant. The result is sure to stimulate some discussion!

Make a herbarium:
A herbarium features a number of dried and pressed plant specimens on a sheet of paper or cardboard. Each sheet can contain samples of flowers, fruit, leaves or twigs and in some cases the whole plant.

Students can prepare their own herbarium but each classroom should also have their own. When collecting specimens it is important to remember to take only small samples from a tree or shrub; and at all times use a small knife or scissors when removing plant parts to reduce plant damage to a minimum.

Check out some resources by clicking on the links below:
Make a plant herbarium
Make your own herbarium specimens (A detailed outline of the process)
How to press plants and make a herbarium specimen
Video on how to press plants for mounting
Video on pressing plants – a simple way
In class activity – Preparing a herbarium

Take a field trip:
A field trip to the local botanical gardens can be a great introduction to plant identification and to the adaptations plants have developed in order to survive in many and varied habitats. Visiting the local nature trail is also a valuable experience. For example in Auckland there is the Arataki Nature Trail or the Campbells Bay Urban Sanctuary Nature Trail. Check the DOC website for trails in your local area. However, a trip to the nearest bush can be beneficial too – especially to collect specimens. You may even have a patch of native bush in your school grounds. (Hint – a most useful project is to label the natives in your school grounds)

Organise your growing unit:
Sorting plants by type assists in the management of your growing unit. For example Dianne Patterson (Auckland Field Officer) suggests when preparing plants for planting later in the season you can have a ‘hands on’ maths lesson with children, usually working in pairs, undertaking processes such as  –
Measuring: Take all plants out of the growing unit and out of their crates. Using a ruler measure plant height, placing plants over 30cm to one side and plants under 30cm to another.

Sorting: Sort plants by type (eg: all manuka together, continuing until all plants are placed in their respective groups).

Arranging: Place plants under 30cm back in the growing unit, keeping plants of the same type together in rows or crates. Place plants over 30cm tall in crates underneath, around outer edge of the growing unit, where they receive water from the unit’s irrigation system, ready to be picked up by the  landowner a couple of weeks ahead of the planting day.

Labelling: Label each crate with the species name.

Estimating: Ask the students to estimate how many plants there are. Compare the result obtained by counting.

Counting: Split the students in two groups, one counting plants of each type over 30cm and the other each type under 30cm. Explain that each crate has the same number of plants (for example each milk crate will hold 4 x 5 planter bags = 20 PB3 per crate) so the children can count crates rather than individual plants.

Recording: Ask the children to record the number of each type over 30cm and under 30cm and write the number on a plant count sheet. In this way you have a record of how many plants are ready for planting out, how many manuka over 30cm, etc.

Back to Te Māra a Tāne