Root damage explanations

[Zaskia]

Hi, I've tried looking around the site and using google but I always end up with the wrong search results. Could someone explain the following to me please? I'm trying to understand how the roots work in these two instances.

If a root has a break but is still connected by the inner thread:

How does that affect the end part of the root?
Will it slowly die off?
Can it still do its job properly with regards to water/nutrients?

If the roots are firm but yellow/cream/very light brown and not becoming green at watering:

How unhealthy are they?
Can they revert back to the usual silver/green?

Thanks!

[estación seca]

Phalaenopsis roots have a thin brown water conducting portion inside a thick, firm but spongy layer of non-living cells called velamen. The velamen collects and holds water so the central thread can take it up.

Growing roots are green at the tips, where cells are dividing. Fresh velamen is white. It ages to brown, but is still able to function. Newer velamen turns green when watered, but older brown velamen may not.

You can't tell whether a brown orchid root is alive or dead unless you look at it under a microscope. I have seen Phals with only very old, brown and hollow roots, which nevertheless kept well-hydrated leaves, indicating the roots still functioned. For this reason I don't cut off old roots.

When a root breaks, the dead velamen breaks, but the central root usually doesn't. Those can still take up water. Again, I don't cut them off.

[Ray]

Concerning the “roots that don’t turn green”, chlorophyll is not present in all roots. Those that are submerged in the potting medium will never see light, so why would the plant waste it’s resources to create it?

[Zaskia]

Thanks a lot estación seca! You explained nicely and I have a better picture of what happens now.

---------- Post added at 03:07 PM ---------- Previous post was at 03:06 PM ----------

Originally Posted by Ray

Concerning the “roots that don’t turn green”, chlorophyll is not present in all roots. Those that are submerged in the potting medium will never see light, so why would the plant waste it’s resources to create it?

It makes a lot of sense when you say it like that! Thank you

[Shadeflower]

I definitely have a different approach to roots than ES but that is the beauty of growing orchids. We all figure out what we like best and if we think the orchid will approve.
First the stringy bit in the middle is green when it's alive, not brown. If it turns brown it is dead. But there is not much harm leaving the brown stringy bits if one wants to hope they still have life left in them.
The velamen coating can easily turn brown over time which does make it hard to judge if it is still performing its job or not. Pressing it for firmness is a good way of judging in such a case, if it is firm like a banana then it is still alive, if it is soft and squishy like a straw then it has degraded and can be pulled away from the stringy bit. Leaving it risks the degraded velamen causing too much wetness in the pot.

I recently had this happen to a plant I bought last year, the difference is very noticeable. Basically I bought two identical plants. The first I cleaned thoroughly and repotted. The second I got lazy cause I'd spent so much time on the first and I didn't rinse the roots! Big mistake. I'd left tiny bits of bark wedged inside of root cracks and repotted it.
Pretty much all my roots rotted away so now a year later I have one plant that has completely filled the pot and ready for a repot already and the other plant has lost all its roots. It will bounce back now that I have removed all the dead roots that were causing a really smelly soggy condition in the pot.

Breaks are unfortunate but they are not as bad as they might seem, like a plant is perfectly capable of producing lots (and I means lots) of root tips out of many places on an existing root. So if the root breaks if the root is kept in a good humid place where it gets plenty or air and never dries out too much then it will most likely produce a new root tip and carry on growing. I will attach a picture that has produced 4 new root tips on a root that got damaged as an example. I actually took this picture because the root reminded me of that sloth from "ICE AGE", maybe you can see the resemblance

[Zaskia]

Oh wow those little roots branching out are adorable! I definitely have a thing for roots, especially the type that Phalaenopsis have.
It really seems like orchids are able to bounce back from terrible situations if they are given the proper care. Very encouraging to a beginner like me who makes mistakes. I just wish I hadn't tried so hard to fit it in the pot I had but I none of the shops around seem to sell transparent pots, let alone different sizes. I think I'll stick to my five orchids (all bought this year) and make sure I can take care of them before I get any others. Read up on some books too...
Thank you for taking the time to answer so many basic questions!

[estación seca]

A lot depends on the humidity in your growing area. Inside my house the relative humidity is between 20%-40% depending on how many rescue dogs I have at the time. Exposed Cattleya and Phal roots always shrivel up and turn brown. The ones inside the pot are healthy. In my sunroom, relative humidity 60% and up, exposed roots remain fresh and green/white for many months before turning brown. Most homes here are air conditioned or heated for most of the year, so few Phals here have nice looking visible roots. In more humid parts of the world they have big fat roots.

[Zaskia]

It's pretty dry in my home during winter as well with all the heating etc. The current exposed roots seem to be silvery for now. Maybe that will change this winter. In any case, when new roots start growing from the top, it is very sweet to look at. I have very few orchids so I can spend way too much time looking at them. I'm guessing you have very many!

I originally come from a tropical country and really wish I'd had an orchid or two then! Lots of stray there and my sister does her best to help. It's great that you helps with rescues!