Hello,
Any insight would be appreciated! I'm confused about the recommendations for spacing some trees. Around March 2020, some Komet austrian pine were planted outside our kitchen windows for privacy. We have 2 trees in front of each of the 2 kitchen windows (a pair in front of each window for a total of 4 trees). My mother just visited and said the trees are too close together.

I looked it up. For Komet austrian pine, the spread is supposed to be 3-4 feet, and the spacing is 2 feet.
For each pair of trees in our yard, the trunks are indeed spaced 2 feet apart.

Why should they be spaced 2 feet apart if they spread 3-4 feet? Won't they be cramped?
Should we replant them in the fall or are they fine as they are?
Also, how can I prevent infestation from bugs?
Thanks!

2' is too close.
At maturity they can be 4' wide. At 4' wide, I would space them 5' apart. You really do not want them touching each other. Even 6' would be better.
3-4' apart is better then 2', but not ideal.

You can not prevent insect damage. You are just better off and see if anything attacks them first. What if you spray and nothing ever attacks them. What we don't need is spraying when we really do have to.

Thanks! I don't understand why gardenia.net would say spacing 24". So should I ask the landscapers who originally planted the trees that they made a mistake and need to replant this fall??

shountras said:Thanks! I don't understand why gardenia.net would say spacing 24". So should I ask the landscapers who originally planted the trees that they made a mistake and need to replant this fall??

Gardenia.net recommends 48" spacing for the Komet Austrian pine. 4 feet.

I doubt if they will admit to a mistake. In fact, they might get very testy!
If you want to move them, you'll have to do it.

3-4 ft spread means how broad they get in total. So if you look at a tree from a bove as a circle, those 3-4ft would be the diameter with the trunk in the center. So half of that (2ft) is the radius.
So two trees who each get 4ft wide will be spaced at 2ft from each other measured from trunk to trunk (= radius) so in theory they'll just meet at their respective ends.

But two trees side by side will generate 2' each, for a total of four feet.
Plus if you look at these guys on-line, they are dense near the base. A little extra space providing air movement could prove very helpful in maintaining good health.

BigBill said:But two trees side by side will generate 2' each, for a total of four feet.
Plus if you look at these guys on-line, they are dense near the base. A little extra space providing air movement could prove very helpful in maintaining good health.

You got me there. I stand corrected.

Math was never my good subject.

Heck, not many subjects were good for me! Science yes.
Dismissal bell? Yeah I aced going home!
Lunch. Well I went home for lunch so I did good with that.
Oh, I was a PRO at riding the school bus 🚌!!

I was just correcting the math error when I saw Bill beat me to it! And I agree with Bill: even 4 feet is crowded. I have a neighbor who keeps planting more saplings in his yard every chance he gets with no regard to how big they're going to get. Gonna be an overcrowded mess in a few years.

I think the question about who moves the trees is who made the decision to plant them that close. If the homeowner directed the tree-planters to do it, it's her/his mistake. If the landscapers/tree-planters made the decision, they should move them.

This is very helpful discussion - thank you so much!! So, the landscaper drew a plan that showed the 2 pairs of trees next to each other. I signed the plan. However, it did NOT state how far apart they'd be planted, just showed circles next to each other infront of the kitchen windows. So I'm thinking they planted them too close by their own discretion, and I don't think they can say I signed off on it since the plan showed no dimensions...
I'll ask them to move it, and get the builder to lean-in if needed.

Good luck with everything.

Sorry one more - what happens if the trees aren't re-planted for more space this fall? Will they grow into a funky shape or be stunted?

Neither of those will happen immediately, but as more time goes by, the roots will become more established and the stress and risks inherent in transplanting will increase. So, yeah, they might have some growth setback, but it will probably shake out in the long run. This fall would be better. For you in Denver, that should probably be mid-Sept given that your frosts can be expected by mid-October (yes?).

A lot depends on their size. How big are the trees? Were they in nursery pots before planting? What size?
(10, 15 gallons?)

Yes I think sept-oct is the time for Denver based on my internetting... The trees are currently 6 feet tall. They seem healthy to me - they're very green. Probably they started in nursery pots but I don't know for sure or how many gallons were in the buckets. Based on that info, you think I should just leave them where they are or do you think moving them in fall will likely make a significant difference?

shountras said:Sorry one more - what happens if the trees aren't re-planted for more space this fall? Will they grow into a funky shape or be stunted?

I might have misunderstood your question. I thought you meant this fall vs next spring. Do you mean leave them permanently two feet apart? Here's what could happen: one or both will lean away from the other; the sides facing (bumping into) each other will suffer thinning growth or branch die-back; the risk of disease or environmental ailments will increase because of reduced air/light between them; most certainly that beautiful conical shape will be imbalanced.

Any or all of that might not manifest for a couple of years. It would be worthwhile to get an arborist or reputable landscaper to evaluate them on-site.

Arico said:3-4 ft spread means how broad they get in total. So if you look at a tree from a bove as a circle, those 3-4ft would be the diameter with the trunk in the center. So half of that (2ft) is the radius.
So two trees who each get 4ft wide will be spaced at 2ft from each other measured from trunk to trunk (= radius) so in theory they'll just meet at their respective ends.

Uhm...wait a minute...if each tree has a 2' radius and you are planting trees in-line that would be 4' between each tree. No?
That's how I have always interpreted it - and then ignored my good sense and planted too closely anyway. Incorrigible.

EDIT-
Sorry, Arico. I did not see that Bill had already posed the same question/point. Nevermind.