Honeydew is a sweet and sticky liquid excreted by certain insects, usually aphids. When these insects pierce the phloem of a plant with their needle-like mouthparts, the sap—which is under pressure—shoots into the food canal of the insect, forcing the previously ingested sap out the other end. Yes, you read that right. Honeydew is fast-tracked bug poop.But it’s not that bad. Trust me. Aphids are dependent on sap for all their nutritional needs, including protein. But plant sap is mostly water and sugar with just a fraction of protein—about 1 to 2 percent of the volume. So the insect must eat large amounts of sap to get enough protein, so what comes out is very similar to what went in—minus a few amino acids. Technically, the substance cannot be called honeydew unless it’s been run through a bug’s digestive tract. Sap that just oozes from a plant is called sap.
The honeydew that is expelled lands on leaves, branches, needles, or even on the ground under the plant. This processed sap is coveted by other creatures, including ants and bees. Although honey bees prefer floral nectar, during times of dearth—especially in the late summer—they will often collect the honeydew, transport it in their honey crop, and process it just like nectar. Yum.
The liquid in honeydew evaporates quickly, so honey bees are more likely to collect it in the mornings or evenings. The bees treat the substance like nectar so it is often mixed together with the nectar from flowers. As such, it is not really noticeable in the finished honey.
Honey made almost exclusively from honeydew is known as honeydew honey, forest honey, bug honey, flea honey, or tree honey. Sometimes it is named after its primary component, such as pine honey, fir honey, oak honey, etc. It is generally dark, strongly flavored, less acidic, and less sweet than floral honey. It is prized in many parts of Europe and in New Zealand, often commanding high prices.
Not so great for bees
Oddly, honeydew honey is not considered good winter feed for bees because it can be quite high in ash, a primary cause of honey bee dysentery. Beekeepers often remove honeydew honey from their hives before the onset of winter.
The amount of honeydew in your honey depends on the plant species that live nearby, the climate, and the local weather. If floral nectar is plentiful all year long, honeydew collection will remain insignificant. In some regions, however, such as Germany and northern California, honeydew honey is quite common. Like floral honey, honeydew honey varies remarkably with its source. Its flavor, color, sweetness, consistency, nutrient content, and tendency to granulate are dependent both on the plant and the insect that collected it.
Plants that produce the sap that feeds the insects are mostly trees. Certain species of ash, basswood, beech, cedar, chestnut, elm, fir, hickory, larch, maple, oak, pine, poplar, spruce, sycamore, and willow produce honeydew, as does black locust. A few forbs produce honeydew as well, including alfalfa, cotton, currants, grapes, gooseberries, and sunflowers.
In Portugal there is a considerable amount of honeydew, oak and similar trees honeydew to be more specific, in late summer, as you say, but in the case of oaks i’ve never noticed that the bees collect it after aphids! Seems to me that they harvest it directly from the tree, perhaps this is what you call “sap”.
In fact it is a very dark honey, and it’s harvest can be maximized if we give the bees empty drawn comb for them to store the honeydew.
I love this kind of honey! 🙂
You can see pictures of it at this links:
Congratulations on your very good site!
Hi. I have a young willow tree about 6 ft high. Down at the base of it I have Black Willow aphids covering a large area on several of the branches. I have now noticed that it looks like I have a bees’ nest in some stones near the base of the plant too. I am worried that they might harm the bees, they are not used for honey making, but I still feel sorry for them. As I have tried to make my garden “bee friendly” as possible by planting wild flowers. Please can you advise whether I should get rid of the aphids? Can they cause bee dysentery? Please help me save my BEES!! Thanks for your help and your site.
I don’t think the aphids and the bees will affect each other. The aphids will not cause bee dysentery. If you want to get rid of the aphids, try washing them off the branches with a garden hose. Certainly anythings else you apply to them could have a larger negative effect on the bees than the aphids themselves.
This morning I noticed bumble bees feeding on the honeydew excreted by scale insects on our yuccas. Is this normal? (I’ve only ever saw wasps feeding like this.)
Yes, it’s normal. Bees will collect nectar (or other sweet substances) wherever they find it.
Hi, I was wondering if someone can answer my questions regarding honeydew in beekeeping:
1. Is there a way to remove honeydew out of frames when it has already crystalized?
2. What to do with honeydew if I consider it as an unwanted product? Do I throw it away or is there a way to make it useful?
3. Can bees be saved if there is already crystalized honeydew inside? If yes, how do I proceed with it?
Thank you in advance, any answer is kindly appreciated!
I’m not sure I understand your question. Do you live in an area with lots of honeydew? Usually, the bees collect some but it gets mixed in with everything else, so it’s just part of the honey.
1. Any type of honey is difficult to move from frames after it crystallizes. I usually use crystallized honey for winter feed. It’s not much different than feeding fondant or hard sugar cakes.
2. Like I said, I have seldom seen honeydew honey that wasn’t mixed with regular honey. I suppose some areas get a nearly pure product, but not many. I would either sell it (it commands high prices) or use it as bee feed.
3. “Can bees be saved if there is already crystallized honeydew inside?” Saved from what? They will have no problem with it. This is clearly a human problem, not a bee problem.
Thank you for your response!
No, but this year honeydew appeared, and my grandmother is out of her mind ahahah. (It does not appear every year).
Since it is not a lot to make it into honeydew honey, my grandmother wants it out (because it crystallizes easier and faster than regular honey).
What I meant is, I’ve read up on honeydew and some sources mention that it is dangerous to use it as winter feed because it causes dysentery (some mention constipation, the opposite). Is this true?
That’s why I asked what to do with it. Is there a way to turn once crystallized honey into liquid, while in the frames (hot knife or something like that) so that it could be easier to get the honey out of the frame?
Thank you once again for your response 🙂
Okay, I get it. Dysentery is caused by the ash in honey or honeydew. Ash is made of minerals and other things, but the amount of ash varies by plant. So I suspect that some honeydew honey has more than others and so some may cause more dysentery than others. One hint is the color. Darker honey has more ash than lighter honey.
Crystallization has to do with the proportions of different sugars in the honey or honeydew. Honey high in fructose is slow to crystallize and honey high in glucose tends to crystallize fast. Again the type of sugar varies according to the plant species.
But your grandmother is probably familiar with the honeydew in your area, and it is probably similar from year to year.
I don’t know how to make crystallized honey liquid again while it’s still in the comb. I don’t imagine a warm room would do it. Sorry, but I just don’t know.
Well, I thought it would be a bit of a stretch 😀 I understand now, we got some oaks here and there, so I should check its sugar type, right?
Thank you Rusty, much appreciated!
In Spain, this type of honey is produced in places of great environmental importance. I will highlight the honey from Las Obreras de Aliste, you can learn more about it on its website http://www.lasobrerasdealiste.es
I have a fair number of bees that seem to be feeding on my fir tree. Is this normal?
Honey bees and some native bees collect sap from coniferous trees. Honey bees use it to make propolis, and some native bees use it to protect their homes from water damage.
Hello! I just discovered your fabulous website and am enthralled. I have a question. On a Gaura plant the other day I noticed that the honey bees were ignoring the normal nectar collecting areas and going for something on the stigmas. All of the other numerous native bees were feeding as usual. I know that the stigmas release a sticky substance on which to trap pollen and wonder if there is something besides sugars that the bees are going for. Proteins, enzymes, scents?
Thank you for your amazing and informative site! It is a treasure trove for this nature nerd. 🙂
Bees use plant sap for any number of things, so it could be that they were collecting it to use as cement or waterproofing.