Ok. Let's play with this.

We're estimating the tree bramch at 20-25 pounds? That's between 9.3 and 11.34kg for metric users like myself.

Let's use something we all know. A bowling ball.

Now a bowling ball has no limit on its lower weight but for certain leagues (such as the ones in my area) the heaviest a ball may be is 7.2kg.

Ok. Let's play with those numbers then.

Assuming you are correct (and with no offence intended I disagree with what you say.) Let's bring it into something we all understand.

A bowling ball.

Now. In my area, there is no lower weight limit on balls but they may not exceed a weight of 7.4kg(we'll make it 7kg even for clarity). So 13ish pounds. Not much huh?

Until the biggest badass in history comes in and kicks you in the face.

Motherfucking Sir Isaac Newton.

You see, when you drop an object, it will begin to gain speed and kinetic energy because we don't live in a vacuum. If I were to drop that ball on your head from 1mm above, you would have a sore head, maybe a sore neck and I would have a broken nose (I assume).

Now if I dropped that 7kg ball from one meter, it would hit you at a speed of 15.94km/h and with 68.6 joules of energy.

Now. That branch did not fall from one meter. It fell from at least 6 meters. So we'll go with your low end guess of 9kg.

6 meters and 9kgs.

The object is falling at a speed of 39km/h with an energy at impact of 529.20 joules.

That's another way of saying 390 foot pounds of force btw.

Weight + height is the dangerous shit.