A BEWILDERMENT IN (at least) TWO PARTS

The ivy I'm examining is on this old elderberry tree.
We could equally well be examining the lichen on it or the insects boring holes in the trunk.

Remember I'm always saying I don't know anything? It's (almost) true. But there's a possibility (maybe a niggling hope) that one day I'll learn. I don't mind this much. Indeed I revel in it. One can get bogged down in facts.

I'm grateful that those who make medicines or collect mushrooms know what's what. I would never try either. The pleasure of ignorance has its limits! I buy veg. from an organic veg. supplier (you can see their emblem in the side-bar) and the only medicine I'm ever likely to concoct is honey with lemon to sooth sore throats. (Not that this works. Sugar makes me cough.)

Here you can see the little roots which attach ivy stems to trees.

This not-knowing is fine. It's what this blog is based on - the joy of looking, the joy of awe.

BUT I find it really frustrating is when I know I CAN'T understand something however hard I try. When it's as far beyond me as any of the subjects I failed at at school. A mystery that slips through my fingers. I look around and see others busily solving the problem but I don't know where to start. The issue is a sort of blob with no obvious entry point.

Here you can see the marks ivy roots have made in the wood of the elderberry before being
pulled away.

I've spent a ridiculous amount of time peering into flowers trying to see how they change into fruit or seeds. The theory is ok - mixture of pollens. But then what happens?

And if the flower doesn't look like a flower?

Ivy flowers don't look like flowers. They look like clusters of berries. If proper botanists are jumping up and down saying 'of course they look like flowers!' - I'm not the only one who's puzzled. Of those who've stopped to ask what I'm taking photos of not one person yet has realised ivy even has flowers, let alone that ivy flowers in autumn. And because ivy only flowers when it's a mature plant and on the sunny side of it and when the ivy leaves no longer look like ivy leaves . . . sometimes one has to start by persuading them it is it really is ivy we're looking at.

A ball shaped cluster of ivy flower buds just beginning to open.
I promise you that when they do they won't look ordinary flowers.

Ivy flowers are grouped in balls.
I think the little yellow blobs are anthers
emerging from the flower before the (green)
petals open.
(It's only because I've already seen what happens next
that I can say this.)

The language we use about flowers sometimes bewilders me; at times it gives the impression that plants make conscious decisions about their appearance.

'Plants use their bright petals to attract insects. 

'Ivy doesn't need brightly coloured petals to attract insects because it's one of the few plants flowering in autumn when there's little competition for the attention of pollinating insects.'

All very well. But where are its petals?

(I plan to show you where they are next time.)

This year, I think I'm getting a bit further with seeing what's what but there are loads of things I still haven't grasped yet. Can you help me?

1. What does it mean that mature ivy is free standing and doesn't have roots'?

The Natural History Museum site says about ivy

'When the plant reaches maturity it produces rootless, self-supporting stems with unlobed leaves.'

Do I dare find a remote tree with ivy and dig it up (the ivy that is!) when no-one's looking to find out what's happening under ground?

Maybe you have some ivy you don't mind tearing out? (Not pulling down but pulling up.) Then you could tell us what you see . . . ? Please?

2. How does pollination in one place cause fruit in another?

Here's my problem.

Flowers have stamens (little sticks poking up from the flower) and on the end of the stamens are little blobs (anthers) and on the anthers there's pollen (which looks like coloured dust). When the pollen is moved from one anther to another (sometimes on the same plant, sometimes from a different one) it fertilises the flower and it produces fruit. But how? The fertilisation happens on the end of the stamens. You don't get fruits there - you get them lower down where the petals are joined onto the stems. (If they have stems - dum-de-dum!) So how can that be? Fertilisation in one place. Fruit in another.

3. Does Ivy need insects to bring pollen from other ivy plants in order to produce fruit or does it work equally well with all the pollen coming from the same plant?

There's no way I'll be able to tell simply by observing. I need someone to tell me.

_____

It's going to take several posts to get to grips with all this. My observations and your input may mean that what I tell you as wobbly 'facts' may have to be changed as we go along.

Help me out folks? Please look at your ivy. Botanists - tell me (please) when I'm wrong - and the answers to things no-one could know without a microscope. (Anyone got a microscope?)

Already the flowers have changed since I took the pictures for this post. Already I'm accumulating photographs of the insects drawn to their pollen. It'll be a marathon catch up when we get to it.

If you are in the UK - find an ivy plant in flower and walk up close. There are likely to be masses of interesting flies hanging out there at present. Hoverflies are my favourite but there are likely to be loads of others too.

If you are outside the UK - do you have this kind of ivy (Hedera helix) where you live?

(Not 'Poison Ivy (Toxicodendron radicans) - that's different.)

* * *

Readers Coming to the Rescue!

Wa -hey! This is brilliant. On her blog 'Close to Home' Jane Strong has written a post about ivy in response to these very questions! 'Ivy for Lucy'. Thanks Jane. Much appreciated.

Hollis explains flower fertilisation thus:
'Fertilization requires that pollen be transferred to the FEMALE organ, the pistil (not to another anther). Hopefully it ends up on a stigma and then a pollen tube grows down to the ovary where the ovules reside; fertilization takes place if all goes well. That's the basic story but of course it's a bit more complicated -- more here:
Fertilisation in Plants (Wikipedia)'

Here's what Amanda says:

'Hi Loose have been having a go at answering your questions, there seems to be two camps on Ivy.. Pull it down or save it for the bees. 

Ivy can take many years to mature but when it dose it shifts to forming mature branches that produce fruit. There are two types of roots, vine roots when they touch the ground they grow in to the ground ( could this be the bare roots you mention) and aerial roots that help it climb "trees".
Have found this post on Pollination which is a good read.
http://aob.oxfordjournals.org/content/104/7/1397
and this paper as well.

Pollinator Effectiveness and Fruit set in Common Ivy (Hedera helix (Araliaceae)Hope these help a little.

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You might also like to read the post about ivy on 'Urban Pollinators'.

* * *

It's TREE FOLLOWING in less than a week (7th November) so the next ivy post will be after that.

> > > > > > >

TREE FOLLOWING LINK BOX ON THE 7th NOVEMBER - TREE FOLLOWING LINK BOX ON THE 7th NOVEMBER - TREE FOLLOWING LINK BOX ON THE 7th NOVEMBER - TREE FOLLOWING LINK BOX ON THE 7th NOVEMBER

P.S. Photographs on this blog were taken on the 24th and the 28th of October 2014.

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