almost past the c.a. exam...

[foodforests]

I got 88% overall. Only domain I have to retake is the tree nutrition and fertilisation, which doesn't suprise me... figuring out the fertiliser analysis and applying it to the square footage was the question that got me I am pretty sure... In reality I would just use compost and mulch 99% of the time anyway, but I guess I should be able to figure this stuff out, if I am going to go around calling myself a Certified Arborist...
Does anyone know of a website with similar problems that I could practise on before my retake? I guess I could just study that chapter a bit harder, huh?
sigh...

 

[treeseer]

Hey you passed all but one domain--Congratulations!

The math is tough if you don't use it often, but keep practicing and you'll get it. Why not use a tree in your own yard, and do a real-life practicum?

 

[foodforests]

Well, thanks for the encouragement Treeseer. I would try to practise on my own trees, but how would I know if I got the right answer? I guess if I actually spent the money on fertilisers and risked the lives of my trees I might figure it out by trial and error!

Hey, would it be too much to ask for you to pose a few problems and see if I can do them? I guess it could be an educational experience for more than just myself... Would you up for that?

 

[foodforests]

Thanks Treeco. I appreciate it. I hope I am worth your investment in time.

Okay, so the area to be fertilised is 80feet diameter. Area = 3.14 x r squared.

so, A = 3.14 x 40 x 40
A = 3.14 x 160
A = 502.4 square feet

Right?

Dr Shigo's recommended rate is 2 lbs N /1000 ft.

Hmm, so for 1000 square feet, using 10.10.10 you would need 20 pounds. I think.

So if I multiply .5024 by 20 pounds, I get 10.048 pounds.

Right?

:bang: or

 

[BostonBull]

I dont know anything about fertilizing yet but I gave your math a real quick look and it seems you have the right answer, but the decimal is in the wrong spot.

 

[vharrison2]

Hey, good job so far! Keep at it!

 

[treeseer]

40 x 40 = 1,600

Keep working it.

It may be just a zero that got dropped, but a zero is not nothing!

You got the right idea though.

Spend $5. and get the Fert BMP to study with.

 

[foodforests]

Well, that is typical. Close, but no cigar.

Okay, try, try again.

Area to be fertilised ; 90 ft diameter
3.14 x 45 x 45
3.14 x 2025
= 6358.5ft2

rate is 2.75 lbs N / 1000 ft2

so, 2.75lbs N x 6.3585
= 17.485 lbs N

To get 17.485 lbs N out of a bag of 20 - 15 - 15 , God I find this hard, I need to multiply 17.485 lbs N by 20%? No...

For every 1 pound of 20-15-15, I have 1/5th of a pound of nitrogen. So, Oh shucks, can't I just use compost?

17.485 x 100 = 1748.5
1748.5 / 20 = 87.425 lbs

right?


Treeseer - thanks for the suggestion of the BMP. I actually bought it already, and never even opened it, so I am going to do that tonight!

 

[userdude]

The fertilizer is 10-10-10.

And that'd be organic, right TreeLo/

 

[foodforests]

:deadhorse: So, was my answer correct?

 

[foodforests]

Well, I was basically trying to get 20% of the figure, so I multiplied it by 100 and divided it by 20...

Thanks for your help. I think I can pass the retake...

 

[Sprig]

I thought area was Pi-r-squared? damn, back ta school, and I thought I had trouble with math before now I am really confused, nm, gotta google.
to anyone who got over 60% in highschool math, they were my heros, algebra made me crazy, yep, sure that was it. NM.