Found on Quora

[LCHIEN]

Top is some 1905 Farmhouse 2x4
Bottom current lumber product. Apparently a fast growing tree made for sustainable logging, it is only a few years old, compared to the old growth lumber that took hundreds of years to replace.

What is the effect on the lumber quality?

https://www.quora.com/Is-todays-wood-softer-than-40-years-ago/answer/John-A-Whitehead-3?comment_id=115010939&comment_type=2&__filter__=all&__nsrc__=notif_page&__sncid__=50742365007&__snid3__=67987800211

[Slik Geek]

Given the closer growth rings, I would expect that the old one would be harder (assuming they are of the same type of tree).
The new one certainly would be less dimensionally stable with moisture changes (the old one is rift sawn).
What is puzzling to me is that I have found 2x4s from 70 years ago tend to be closer to an actual 2" x 4" dimension (larger than today's 1.5" x 3.5" "2x4s").. I would expect something which was about 120 years old to be even closer to an actual 2" x 4" dimension, or at least as large as the 70 year old 2x4s I have seen - yet the photo indicates both boards have roughly identical dimensions.

[leehljp]

What is puzzling to me is that I have found 2x4s from 70 years ago tend to be closer to an actual 2" x 4" dimension (larger than today's 1.5" x 3.5" "2x4s").. I would expect something which was about 120 years old to be even closer to an actual 2" x 4" dimension, or at least as large as the 70 year old 2x4s I have seen - yet the photo indicates both boards have roughly identical dimensions.

I remember when the change took place - 1964. (I looked it up) I didn't get the "memo" but remember purchasing a few 2x4 for a project as a teenager while in high school. I looked at the 2x4s and my mind noticed something different. I measured and thought they sure were small. Then when I got home, I measured a few shorts/ends that dad had on hand, and there was a difference. I don't remember the size of the shorts dad had but do remember specifically that instance because it caused some confusion on my part. I never forgot that.

[LCHIEN]

That was also a question I had about that picture... how is it that the 1805 lumber is the same dimension as modern 2x4? Coincidence? Modified? 2x4 were shrunk from literally 2" x 4" finished size in the 20th century to today's 1.5x3.5 inches.

But the original point was the relative size of the annual growth rings was astounding. Presumably the newer lumber is a result of managed forestry practice, planting fast growing trees for sustainable harvest in a handful of years (as opposed to 200 years).

[twistsol]

It also depends on where this lumber was harvested. My brother has an 1858 house nearby and the 2x4's are all oak and I would bet look very much like to top example and likely harvested very nearby. The bottom example also has the heart in it and the first few years of a tree's life have very rapid growth which tends to slow each year as the tree gets older. I can't tell how close to the heart the top example is, but there isn't a lot of curve to the grain.

Also, 2x4's aren't used horizontally in framing (other than top plates with a 16" span) and their strength needs to be compressive along its length.

[leehljp]

The 2x4s in the walls of our nearly 100 year old house are larger.

The PROBLEM is that the current size 2x4s were in existence WAY before 1964. There just wasn't a "Standardized" size before then. Many full size 2x4s were not planed - which is what I have seen in many old houses, and what we used in our barn and storage buildings on our farm when I was growing up. We did have some planed 2x4s but they were larger, than the current standard.

[LCHIEN]

Just counting it looks like there are more than 6 times as many rings per length in the old growth lumber... Means the managed lumber grows 6 times as fast.

[dbhost]

And all I ever see on quora are escapees from the sanitarium... I wonder what that says about me?

[capncarl]

I think the old saying that something grows like a weed should be replaced with something grows like a pine. When we bought our property and built our house it was in a planted pine forest, Loblolly pines. The trees were maybe 20 feet tall, perfect for harvesting pine straw. Growing 2 feet per year, 10: yrs old, and would have made a decent size fence pole. Now the trees are about 30 years old the 20 trees that were cut down were nearly 75 feet tall and would produced some nice long lumber. They were carried to a sawmill rather than a pulp paper mill. This pine warps, splits and twists so bad that even Lowes and Home Depot won’t sell it! It’s also know to attack houses when blown down by hurricanes and tornadoes.

[twistsol]

This is a random sampling of the offcuts from last summer's shed project that was still in the burn pile in my daughter's garage.. This lumber all came from Home Depot June of 23.