Know Your Nems - Answer thread
Go to the Quiz thread first if you want to take it. The answers are below.
Here you go.
Number 1 - Yes
This should be an obvious one. Notice how the damage starts in the petiole and continues into the leaf. The giveaway, however, is that one vein that continues up into the leaf. Notice that the dead tissue is delimited by the veins.
Number 2 - No
This is typical tissue damage of a Hosta getting ready for dormancy. The necrotic or chlorotic tissue is not vein delimited.
Number 3 - Yes
This one is really subtle and would be easy to miss, but the key is that the damage is limited by the veins.
Number 4 - Yes
A little more subtle than #1 but from the same plant. The tissue damage on the margins of the leaf are probably not nem damage. However, the brown streak up the petiole continuing into the leaf veins at the "throat" of the leaf is a characteristic sign.
Number 5 - No
Sun damage or just getting ready for dormancy. The tissue damage on that vein on the bottom is not limited by the veins. Nems will eat through the entire section between the veins.
Number 6 - No
The necrotic tissue is not vein delimited.
Number 7 - No
Once again the damage is not vein delimited.
Number 8 - No
That light green streak in the plant is just part of its streaking. The necrotic tissue is not vein delimited.
Number 9 - No
I'm not sure what this is but I'm pretty sure it's not nem damage. The brown area goes up the throat of the leaf, but it's rough on the surface and doesn't seem to spread.
Number 10 - Yes
OK, I cheated this is a Brunnera. Nems do not only appear in Hostas. They are in many many different plants including weeds. However, they appear differently in plants like Brunnera which has palmate veins and not parallel veins. The tissue damage is still vein delimited in Brunnera, but looks different because of the different vein pattern.
So how'd you do.
100% - You're a Nematode Ninja, stalking your garden with a shovel and a bottle of Zero-tol, while the water boils on the stove.
80% or above - You know what you are looking at, but you may not care if your plants have nems, or you've resigned yourself to living with them.
Below 80% - You need to go shopping for Hosta at a local nursery in August or September in the North (earlier in the South).
Don't worry I was in the garden of a fellow Master Gardener a few weeks ago and she had no idea what nematode damage looks like.
It's a nematode world, we're just living in it.
This post was edited by steve_mass on Mon, Oct 7, 13 at 13:41