seed collecting almanac

Coprosma rigida

Coprosma rigida is one of a group of shrubs and small trees superbly adapted to flood zones. This is a particularly challenging environment because along some of our rivers and around wetlands the ground might be waterlogged for several months during the winter then the sandy or silty soil might be quite dry all summer. This combination of conditions is too harsh for so many trees and shrubs, giving Coprosma rigida and a few other species  a really competitive advantage.

Unfortunately these riparian margins are ideal productive land so healthy intact forest ecosystems along our rivers and around our wetlands are rare.  Coprosma rigida (sorry no common name) has become uncommon. It is found in small pockets of low lying ground on river islands or below steep banks which is hard to get to or farm profitably.

The few remaining Coprosma rigida along our rivers are ageing and occasional browsing seems to discourage young recruits. In the time I have been looking out to collect seed I have seen several grow old and fall over and none have grown up to replace them. So to make sure I can get enough seed to reestablish forest the way that I think is important I am having to augment the seed I can collect from wild sources with seed from shrubs I have planted in protected areas.

Ecosourcing ideally collects seed from a representative sample of a local wild population. I have to be really careful when collecting seed from my planted sources that I have a record of the original wild source as well as the collection site. If we want to restore resilient authentic ecosystems this may be our only option as we continue to modify the natural world.

makomako / wineberry  

(Aristotelia serrata)

Wineberry is a colonising small tree, found particularly around forest edges and disturbed areas. Because it grows so quickly yet lives several decades, grows up to eight metres and produces lots of delicious fruit for the birds, it is an ideal coloniser. However, I know of no other tree or shrub so sensitive to both too wet or too dry soil. So, you have to be pretty careful with its placement. The leaves are soft and a bit sensitive to wind but frost is no challenge for this hardy species. Once it is established, there are plenty of seeds and the birds are only too keen to spread them around so before long wherever the conditions are ideal. You will find it there.

From a distance, the flowers are difficult to tell apart, but male and female are on different trees, so only the females bear the dark red or black fruit in clusters. They don’t all ripen at the same time so you have to take special care to just pick the ripening fruit and leave the green ones for later or for the birds.


Fuchsia excorticata

Kotukutuku flower mostly in December and within a month there is a profusion of berries on the trees. From a single flower comes a berry with up to 100 tiny seeds embedded in the succulent flesh.

There are two kinds of trees, having two kinds of flowers. Some are functionally female, having given up the ability to produce pollen, and some are hermaphrodite, with both male and female functions.
This poses the interesting question: what competitive advantages do each have and why are each strategy, equally successful?

Typical kotukutuku habitat
just above flood level on the stream bank

We see kotukutuku all along stream and river banks, where the ground is perpetually damp. Kotukutuku is pretty fussy though, it doesn’t cope at all well with flooding over its roots, so it needs to be planted in the wet seeps along streams but above any chance of being flooded.

Frost is not so much a problem for this, the world’s tallest fuchsia. The leaves might curl up and die in a heavy frost but usually they don’t last the winter anyway.
The stems are fine, sprouting fresh new growth once the chance of frost has passed.