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[VE9VIC]

I plan to install a vertical for 80 m, but it would be among trees (spruces and pins)
to be more specific, there will be trees all around, the closest ones about 4 feet.
I wonder how it will affect my vertical, maybe it won't ?

[WA2ONH]

Here's an article from Carl Luetzelschwab K9LA's Propagation site under the Contesting TAB:
http://k9la.us/

Low Band Antennas and Trees
http://k9la.us/Low_Band_Antennas_and_Trees.pdf

A 3-Page PDF file of approx 31kb size.
.

[VE9VIC]

thanks

[NO9E]

I had a number of 160m verticals suspended from trees and a 80m vertical. Both with elevated radials. Here are my thoughts that partially agree with K9LA article.

1. The top cannot be too close to the tree. Inv V passing thorough a  tree but suspended in the air is fine.

2. My antenna with 1/8 wave radials worked  better than with 1/4 radials. This agrees with simulations. With short radials the feed need to be via a transformer. transformer.

3. 80m vertical was always below a dipole at 60 feet, even for DX.

I use 3 el Hi-Z receive array that has 20 ft verticals a few feet from large pines. I has very  good F/B. With high losses F/B would be poor so the losses mus be low.

[KA4WJA]

Rino,
In addition to K9LA's article, I have a friend who has his 80m (80m/160m) vertical in a tree and it does work well for him.
 

I plan to install a vertical for 80 m, but it would be among trees (spruces and pins)
to be more specific, there will be trees all around, the closest ones about 4 feet.
I wonder how it will affect my vertical, maybe it won't ?

My friend Bob, KC4VO, describes his antenna in detail on his qrz page.
https://www.qrz.com/db/KC4VO

In brief...he has a 47' vertical, with base loading (or sometimes he extends it to a full 64' height) in a 36' tall magnolia tree....(thereby leaving at least the top 11' exposed and in the clear)....fed against many (90?) ground radials.

He is about 130 miles from me, so his 80m signal from his vertical is much lower (15 - 20db) than others in our area (within 200 - 250 miles) using horizontal dipoles....but when we are talking with other friends up North (WI, PA, NY, NJ, NH, etc.) he is always stronger up there, than the rest of us!  (and when we talk to some friends in Europe, here again he is always stronger than those with the dipoles)
Although sometimes he does "extend" the vertical to full height of ~ 65', and of course bypasses the base loading, and he picks up some additional gain...and, while you'd not think to be noticeable, for us close-by here in Florida its usually about a 2db increase, and for those up north or in EU it's even more... 

Have a look at what he has.
https://www.qrz.com/db/KC4VO


Hope this helps.

73,
John,  KA4WJA

[K5LXP]

Trees represent some characteristics of conductors and insulators but are closer to insulators.  So can't say any coupling/attenuating effects at HF are "zero" but are as close to zero as you can measure in practice.  When I operate portable a common antenna configuration I use is an end fed half wave suspended vertically in a tree (like a 100'+ ponderosa).  So not just near the tree, it's *in* the tree and as close to parallel to it as you can get short of stapling the wire to the trunk. Performance is excellent, and no observable effects of any tuning shift.  When you're in a stand of Ponderosas there's no getting away from tall trees in all directions anyway, so the idea of seeking out an "optimum" location vs a very good to excellent one is moot.  Put the thing up, and enjoy all the performance and capabilities a nice antenna offers.

Mark K5LXP
Albuquerque, NM

[WA3SKN]

I have read many articles on this... most of which are HIGHLY flawed.
I think you will find that there will be no real problems for HF.
The bottom line is what is practical for your situation.
And, by using two wires on either side of the tree trunk in a cage arrangement, you might get the bandwidth to cover all of 80 meters.
(the losses encurred are simply the sap just under the bark creating a lossy conductor that causes a directional pattern to form... a two element array.  It changes the antenna's non-direction pattern to a directional pattern, slightly.)... nothing to worry about!
Again... what is practical for you?

-Mike.

[KD4S]

Seven years ago I moved to a neighborhood with HOA restrictions. I installed my SteppIR vertical in backyard using bungie cords to strap it to a tree which made it almost invisible. I had to use the "create/modify" feature to shorten the antenna for resonance on each band. In fact, it was six feet shorter on 40 meters. So, yes, trees affected the antenna but was able to make lots of contacts.

After a couple of years I found the neighbors to be friendly. I moved the antenna to be in the middle of four trees each about ten feet away from antenna. I painted it with camouflage paint and looks like another tree. Now the antenna tunes close to factory settings. It works as well as I can expect and have 300 DXCC confirmed. I installed about 45 radials of various lengths on/in the ground. The ground is in a "flood plain" which is typically wet and probably helps.

I suggest experimenting to see what works for you. Ham radio is a great hobby for experiments. Good luck.

73,
Dick, KD4S

[K0UA]

All I can offer is anecdotal evidence. I have a 30 meter vertical right in a cedar tree and I have 228 countries confirmed on that band and on the 160 meter inverted L, the vertical portion of about 45 feet is in the same cedar tree I have 124 countries confirmed. They are both fed with the same coax and have two elevated radials each.  The vertical portions of the wires (No. 12 house wire) are both interleaved right in the cedar branches touching in many places. So draw whatever conclusions you like from that, but I think they are working pretty well. I am in southwest Missouri near Branson.

[AC2RY]

I plan to install a vertical for 80 m, but it would be among trees (spruces and pins)
to be more specific, there will be trees all around, the closest ones about 4 feet.
I wonder how it will affect my vertical, maybe it won't ?

There will be some influence. But how much - it is hard to say. I do have vertical between trees. I notice some difference between summer (leaves) and winter (no leaves). But the signal difference is less than 1 S unit.

When installing vertical - make sure it is isolated to prevent contact of active element and tree branches. In my case I use fibreglass pole with active element inside it. Rain/snow will make antenna de-tuned. But if you have good antenna tuner, this will not be an issue.

[VE9VIC]

Thanks again to all for the good advices, I read them all with interest.
I got an OCFD on 80 m which I use as an all bands antenna, It is a good antenna,
but not  wonderful on 80 m for DX, 3Y0J is coming as many others, so a little help
will be welcome. In the spring, I have planned to move the 80 m vertical to a better place
with better radials and probably 160 m, for now we haven't much snow yet, so I have a
window to erect a temporary vertical. My power is 100 watts.

[W1VT]

Steve K6OIK has described complex software that will model trees interacting with antennas.  $200 license for HOBBIES.

I use a tree supported top loaded vertical 40 ft high.  Four elevated radials over wet clay soil.
 245 countries confirmed on 80.  I've easily worked DXCC with 100W on SSB/CW.
But, I only have half a dozen trees on a suburban house lot, not a forest.

Zak W1VT

[US7IGN]

Yes, trees affect antennas. But it depends on the type of wood and many other factors. I often use wire antennas in the forest and always have a lot of long distance QSO. Just do it and enjoy!

[N4UFO]

All I can offer is anecdotal evidence.

Same here. About all I have on 160-10m is wires in/between trees (except a temporary experiment) with 30-10m being vertical wires mounted on a fence and hung from a branch just a few feet from a huge trunk. And I am working all over the world. Have worked the current Crozet DXpedition on 2 bands, I have worked all over Asia, Africa and the Pacific. If you want to see pics of mine and how close they are see my QRZ page: https://www.qrz.com/db/n4ufo

[GEORGEMINK]

Just do it and enjoy!

Best advice yet! Hey, if it's your only option than put it up and live with what you have. I'm in the same boat with having to deal with attic antennas. Worse yet it's a small attic!