Welcome to Meteorology Matters. If you want to
understand all the powerful things that shape
our world, especially when we think about weather
and the crazy impact it has and it keeps having,
even later, you're in the right spot. And today
we're focusing on when you get the massive power
of hurricane force winds and they collide with
our urban forests. Ooh. We're going to explore
what happens to those trees themselves and more
importantly what that means for the communities
we live in, you know, both right after a hurricane
hits and in the years to come. Exactly. Yeah.
You know, we got some really interesting information
about how different types of trees handle these
incredible forces. We're going to talk about
the wider effects on cities and figure out some
key lessons for how we should be planting and
managing our urban green spaces moving forward.
Stick with us and you'll walk away with a much
deeper understanding of which trees are really
tough in the face of hurricanes, where the weak
spots are, and how crucial a healthy tree canopy
is for our cities, even after the storm's gone.
Absolutely. And before we really jump in, remember,
you can follow meteorologist Rob Jones on Instagram,
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and on YouTube, follow Rob Jones Hurricane. OK.
You can also find the Meteorology Matters podcast
playlist there for even more insights into our
dynamic atmosphere. Awesome. Okay, let's dive
right in the sheer force of hurricane winds.
It's mind -blowing. It really is something else.
And what I find really fascinating is how clearly
the data shows this power. When we look back
at studies that tracked 10 separate hurricanes,
we saw that urban forest loss varied a lot from
about 11 percent to a whopping 38 percent. And
a key takeaway here is that the amount of loss
was directly tied to how strong the winds were
during each storm. Higher winds equal more trees
damaged or totally gone. Makes sense, right?
The stronger the wind, the more damage. But it's
not all about wind speed during a hurricane.
There have to be other things at play, too. Absolutely,
you're spot on. While wind speed is a major cause
of damage, the other conditions that come with
a hurricane, like how much rain there is and
how long the storm hangs around, also have a
big effect on urban forests. Right. Think about
what happens when a ton of rain falls. The ground
gets completely saturated. And that's gonna affect...
how well those tree roots are holding on to the
soil. They're not going to have as good a grip.
Exactly. When the soil gets super soaked, it
lessens the friction between the tree roots and
the ground around them. Right. This weaker grip
makes it much easier for even winds that don't
seem that strong to push trees over. Interesting.
And it's not just the weather during the storm,
the specific traits of the trees themselves,
like what kind of tree it is, how old it is,
how healthy it is, and even its shape all contribute
to whether it can withstand those powerful winds.
So like a young healthy oak tree is probably
going to fare better than an older, maybe not
so healthy pine tree when a hurricane hits. Exactly.
And the place where a tree is growing matters
just as much. Things like how deep the soil is,
where the water table sits underground, how compact
the soil is, and even how many other trees are
nearby can all influence if a tree survives a
hurricane. Now you mentioned the density of the
surrounding tree canopy. How does that play into
a tree's vulnerability? Here's where it gets
interesting. Think about Pensacola, Florida,
which has traditionally had older and denser
tree canopies versus Miami, which tends to have
younger, more spaced out tree cover. OK. Research
has actually shown that Pensacola had more damage
to its urban forest during hurricanes compared
to Miami. That's kind of surprising. You'd think
that a denser canopy would provide more protection.
as a group. Yeah, you might think so at first,
but remember we talked about soil depth. In places
like Miami -Dade County, the soil can be super
thin. Sometimes, only about a foot deep, trees
in that kind of shallow soil are naturally more
likely to get uprooted no matter how dense the
canopy is around them. This really shows how
interconnected all these factors are when we're
trying to figure out how vulnerable a tree is
to hurricane winds. So the key takeaway is it's
not just about how many trees you have. but where
their roots can actually grow, even a dense canopy
is vulnerable if the soil is shallow. That makes
a lot of sense. I remember reading something
about trees growing in groups having a better
chance of surviving. That seemed really interesting.
It is super interesting. The research done after
hurricanes Ivan and Jean showed something pretty
clear. Trees that were growing in clusters of
five or more. And by clusters, we mean about
10 feet apart, but not in a straight line. They
had a much higher survival rate than trees growing
on their own. We're talking about a boost of
around 10 percent in both of those major storms.
Ten percent can make a huge difference when you
think about how widespread the damage is from
a hurricane. Why would being part of a group
offer more protection? The main idea is that
it's all about having enough space for the roots
to grow. I see. When trees have room to spread
their roots and growing in a group rather than
being totally isolated often means the roots
can connect and form a stronger network. They
can really anchor themselves in the ground. So
it's probably not so much about physical support
from nearby trees but more about having strong
roots from having enough space to grow. That
makes sense. Intuitively stronger, more widespread
roots would make it harder to uproot a tree.
So for planting in the future, it seems like
we should think about making these groups of
trees instead of just planting them one by one.
Exactly, and it's not just about planting them
close together. Right. Having a variety of tree
species mixing in trees of different ages and
even including shrubs and smaller trees underneath
the main canopy, all of that can make a community's
urban forest much stronger. Okay, so diversity
and planting in groups seem like good strategies.
What about the types of trees themselves? Are
some species just naturally better at handling
strong winds than others? Absolutely. Our studies
looking at what happened after those 10 hurricanes
have consistently shown that some types of trees
are just better at handling hurricane force winds.
And by wind resistance, we mean their ability
to stay standing and alive, even in those crazy
wind speeds. They're less likely to be uprooted
or have major damage like a broken trunk or big
branches falling off. And I imagine that information
is super valuable for communities that are either
rebuilding after a hurricane or are trying to
prepare for future storms. Oh, it's crucial.
One of the big goals of this research is to make
practical lists of these tough tree species,
and to make this information as useful as possible.
These recommendations are tailored to different
parts of the country that get hit by hurricanes.
We've got specific lists for the southeastern
coastal plain, which basically lines up with
USDA plant hardiness zones eight and nine, and
another set of recommendations for the more tropical
and subtropical zones, specifically zones 10
and 11. OK. on both what we've seen on the ground
after hurricanes and expert opinions from arborists,
tree scientists, and urban forestry pros. So
if you live in, say, coastal Georgia, you'd check
a different list than someone living in the Florida
Keys. Exactly. And knowing which trees don't
do well in hurricanes is just as important as
knowing the strong ones. We found certain overmature
or inherently hazardous trees that have a bad
track record when it comes to surviving hurricane
force winds. In North Florida, some examples
of these weaker trees are sand pine, pecan, laurel,
oak and water oak further south in the tropical
and subtropical areas. You might want to be careful
with trees like Queen Palm, Australian Pine Mililuca
Weeping Banyan, and Washington Palm. So it might
even be a good idea to proactively remove some
of those weaker, more vulnerable trees if they're
old or could pose a danger to property or people.
That's definitely a smart move that communities
and homeowners should consider replacing trees
that are on their way out or known to be weak
and strong winds with groups of more resistant,
longer living species, like different kinds of
live oaks, can really help build a healthier
and stronger urban forest that provides better
long -term canopy cover and more biodiversity.
It's like an investment in the future of our
green spaces. Now, you mentioned that laurel
oaks didn't do so well in North Florida, but
that wasn't as clear in South Florida. That's
an interesting regional difference. It is. There
are a couple of possible explanations for that.
One is that the laurel oaks often found in South
Florida might actually be a different genetic
variety than the ones common in North Florida.
Another thing could be the differences in soil
between the two regions. South Florida usually
has sandier soils with less nutrients, which
could mean that laurel oaks there don't grow
as tall or develop the same trunk and branch
structure as their northern cousins. This difference
in how they grow could affect their wind resistance
in different ways. However, it's generally accepted
that live oak trees have super strong wood and
do really well against hurricane winds. It's
good reminder that how well a specific tree species
does can depend on the local environment, like
the soil and climate. It's not a one -size -fits
-all answer when it comes to choosing the right
trees. Now, let's talk about palm trees. They
look totally different from broadleaf trees.
How do they usually handle hurricanes? Great
question as a whole group. Palm trees tend to
be better at withstanding hurricane force winds
than many broadleaf trees and coniferous trees
like pines. Their unique way of growing with
just one central growing point at the top of
the trunk. We call it the terminal bud. That's
a big part of why they're so tough. If this bud
survives the storm, the palm can actually recover
and grow new leaves. even if it loses all the
ones it already has. So if a palm loses all its
leaves during a hurricane, that's not necessarily
the end for the tree. Usually not, as long as
that central bud isn't damaged. Our research
supports this idea. Palms in both coastal plain
and subtropical areas tend to be more wind resistant
overall than lots of other tree types. And this
is important, how they respond to winds can be
very different between different kinds of palms.
Like we talked about earlier, Queen palms and
Washington palms haven't done well in South Florida
hurricanes. So just like with other types of
trees, choosing the right kind of palm is key.
Exactly some examples of wind resistant palms
would be sable palm, canary island date palm,
and manila palm. And one thing to remember with
palms is that you need to keep a close eye on
them after a storm damage to that important terminal
bud might not be easy to see. So it's best to
wait at least six months to see if new leaves
start to grow. You should also watch for any
subtle signs of damage to the root stem or the
bud itself. That's good to know. You might look
at a palm after a hurricane and think it's fine,
but there could be problems you don't notice
right away. Right. What about pine trees? They
were also mentioned as having a kind of unique
reaction to hurricane winds. Yes, pines often
have this delayed and sometimes really surprising
response to the stress of hurricane winds right
after a storm. They can look totally fine, still
green and standing tall. But the scary thing
is they can start to decline and eventually die
months or even up to two years later. We actually
saw this in our research after Hurricane Charlie,
where a big chunk of seemingly healthy South
Florida slash pines and longleaf pines died within
just three months of the storm. Wow, that's a
hidden impact, and it could be really significant
what causes this delayed decline. While we're
still figuring out exactly how it works, the
main theory suggests that it's probably from
subtle internal damage caused by all the bending
and twisting they go through in hurricane force
winds. Those smaller roots might tear without
the bigger visible ones breaking this hidden
damage, can stop them from effectively moving
water and nutrients up to the top of the tree.
Oh, I see. So they might look healthy and green
for a while, but then suddenly show signs of
stress like yellow needles, which can quickly
turn brown and lead to the tree dying. So even
if your pines look OK right now, after a hurricane,
you gotta keep a close eye on them for a long
time after. Exactly. You need to be watching
for any signs of stress or problems with bugs
for months or even years after a big storm. Gotcha.
Pines that have been weakened by the wind can
be more easily attacked by pests and diseases.
Let's switch gears a bit and talk about trees
losing their leaves during hurricanes. It sounds
odd, but isn't it true that sometimes losing
leaves can actually help certain trees survive
strong winds? That's right. It might look dramatic
to see a tree totally bare, but for a lot of
broadleaf trees, this is a way to survive. Hurricane
force winds put a ton of pressure on the whole
surface of a tree's crown, and by dropping their
leaves, those trees are basically making themselves
less resistant to the wind. It's like a sailboat
taking down its sails when there's a big gust
of wind so it doesn't tip over. Exactly. And
it's important to understand that just because
a tree loses all its leaves, it doesn't mean
it's dead. Right. It just can't make its own
food through photosynthesis for a while. OK.
But with enough time and the right conditions,
most of these trees will grow new leaves, which
is a good sign that they're recovering. This
new growth usually happens within a few months
after the storm or by the next spring or early
summer. Are there specific types of trees that
are known for dropping their leaves in strong
winds and generally doing pretty well during
hurricanes? Yes. In North Florida, the live oak
is a great example. It sheds its leaves and smaller
branches easily and is generally really good
at handling strong winds further south in the
tropical and subtropical areas. The gumbo limbo
tree does something similar. It drops its leaves
and is known for being wind resistant. However,
it's important to remember that this leaf dropping
strategy isn't good for all kinds of trees like
we talked about earlier. Coniferous trees like
pines might not recover well if they lose a lot
of their needles. Okay, so leaf loss can be a
sign of resilience for some broadleaf trees as
a way to reduce wind resistance. But it's a bigger
concern for conifers. Yeah, that's a good distinction
to keep in mind. Now let's talk about native
versus exotic or non -native trees. Is there
a general pattern in how these two groups tend
to do when faced with hurricane force winds?
There's some interesting data on this. Our research
after a few big hurricanes in South Florida,
including Gene, Andrew and Charlie, showed a
general trend where native tree species had better
survival rates overall and less branch damage
compared to exotic or non -native species. Some
examples of native trees they did well were live
oak, gumbo, limbo and sable palm, while more
vulnerable exotic species included melaleuca,
Australian pine and queen palm. So does that
mean that focusing on planting native trees might
be a good strategy in areas that get hit by hurricanes?
It definitely seems like a smart approach. And
this trend might have to do with the fact that
in the urban forests of South Florida, exotic
trees make up a big chunk of the total tree population.
I see. However, things aren't quite as simple
when we look at other areas. For instance, when
we looked at the impact of Hurricane Ivan in
North Florida, we didn't see that same clear
pattern of native species always doing better
than their exotic counterparts. Why the difference
in those? observations. One possible reason for
this regional variation could be that there are
way fewer exotic trees in the urban forests of
North Florida compared to South Florida. In the
case of Hurricane Ivan, exotic species were only
about nine percent of all the trees studied.
The main exotic species in that region were things
like grape myrtle, Chinese tallow tree, camphor
tree, Bradford pear, and some palm species. We
also saw this trend of native trees surviving
better in South Florida when we compared it to
what happened after Hurricane George. in Puerto
Rico, which had very few native tree species
included in the measurements. It's also interesting
that Hurricane George's was a weaker storm with
lighter winds, and there weren't any statistically
significant differences in survival rates between
the native and exotic species in Puerto Rico.
So it seems like how many exotic species there
are in a region's urban forest might affect whether
we see a clear advantage for native species during
urticaines. That's a strong possibility, and
it shows how complex ecological interactions
can be. Right. And of course, there are tons
of other good reasons to plant native trees,
like their importance for local wildlife and
helping to preserve native ecosystems. Let's
talk more about individual trees. How do things
like a tree's age and overall health affect its
ability to handle hurricane -force winds. Age
and health are definitely big factors that can
make a tree more or less vulnerable to hurricane
damage as trees get older. They naturally become
more susceptible to all sorts of problems like
bugs, diseases, and branches dying back. Older
trees also tend to become less flexible and might
have picked up some minor damage over time from
past storms or other stress which makes them
more likely to break in strong winds. Right.
Our research has shown that bigger, older trees
tend to lose a larger percentage of their branches
during hurricanes compared to younger, smaller
trees. So that big, strong -looking old oak tree
in your yard might actually be at higher risk
than the younger, more flexible trees around
it when a hurricane's coming. Yeah. Unfortunately,
that can be the case. Wow. And it's important
for homeowners and people who manage urban forests
to remember that every tree has a natural lifespan.
Some just live longer than others. For example,
a laurel oak might only live for about 50 years.
years and can start showing signs of decline
and becoming more susceptible to disease as early
as 40 years old. As a tree gets close to or passes
its typical lifespan, the risk of it breaking
in strong winds goes up and the potential for
it to cause a lot of damage if it does fall also
increases. That makes sense. Yeah. So thinking
about the natural lifespan of different tree
species should be a big part of how we manage
our urban forests. Absolutely. Overmature trees
that pose a danger to people or property should
definitely be considered for removal and replacement
with younger, more wind resistant species that
are better suited to the long term health and
strength of the urban forest. Regular checks
for structural problems and overall health by
a certified arborist or urban forester are crucial
for effectively managing older trees in our communities.
And it's not just being old that makes a tree
vulnerable, right? Trees that aren't healthy
are also going to be at a much higher risk. of
falling during a hurricane. Exactly trees that
are already having problems like root decay decay
in the trunk or branches or have a lot of dead
or dying branches are way more vulnerable to
hurricane force winds. Decay which is often caused
by different types of fungi weakens the wood
inside the tree. Visible signs like cracks in
the bark, sunken or swollen areas on the trunk,
dead branch stubs, and even mushrooms growing
at the base of the tree can all be signs of decay
or root problems. Root rot, for example, can
make a tree much less stable. Regular inspections
by qualified arborists can help find these potentially
dangerous trees before a storm even gets close.
So being proactive with tree care, including
removing unhealthy or structurally unsound trees,
is a vital part of hurricane preparedness for
urban forests. What about the physical structure
of the tree itself, things like how the branches
grow and how the trunk develops? That's super
important. Trees that grow what we call codominant
stems, meaning they have two or more main trunks
that are about the same size coming from the
same spot near the ground, are often naturally
more vulnerable to wind damage. I see. These
types of structures can develop weak spots where
the stems connect often with what we call bark
inclusions. Bark inclusion happens when the bark
grows inward between the two stems, stopping
the strong wood fibers from interlocking and
creating a really solid connection. Interesting.
These connections are especially likely to fail
and break in strong winds. So the best structure
for a wind resistant tree is one with a single
strong central trunk. Exactly. Choosing and planting
good quality nursery trees that have one well
-defined central leader and a nice symmetrical
shape is a crucial first step in promoting long
-term wind resistance. And it doesn't end there.
Proper pruning, especially when a tree is young,
plays a huge role in developing a strong wind
resistant structure. Trees that have been pruned
well to encourage a more open and balanced crown
tend to do much better during hurricanes than
trees that haven't been pruned or have been pruned
poorly. So doing pruning the wrong way can actually
make a tree more likely to be damaged by wind.
Absolutely. Things like topping trees or cutting
off big branches in a way that leaves big open
wounds can actually make it easier for things
that cause decay to get in. Old pruning cuts
that weren't done right can become places where
fungi can start growing and weakening the tree
from the inside out. The main goal of preventive
structural pruning is to guide how the tree grows
by shortening and reducing the number of branches
that are competing with the main trunk. This
helps the tree develop a strong central leader
and well -spaced smaller branches. Right. And
of course, picking the right type of tree for
the spot, thinking about how big it's going to
get, and not planting big trees under power lines
can reduce the need for drastic pruning later
on, which could damage the tree. This all really
highlights how important good pre -care practices
are, from choosing the right species to planting
it correctly and taking care of it as it grows.
All of that helps us build urban forests that
can handle hurricane force winds. Now let's go
down to ground level, the soil and the root system.
How do those underground parts help a tree withstand
strong winds? The stuff you don't see that's
holding the tree up is absolutely vital for its
stability. Giving trees enough space in the soil
so their roots can spread out is one of the most
overlooked but fundamentally important things
when it comes to a tree's ability to resist being
uprooted by strong winds. Makes sense. Our research,
including studies after Hurricane George's in
Puerto Rico, has clearly shown that trees with
more uncompacted soil for their roots to grow
in had much higher survival rates during the
hurricane. So more space for the roots to spread
out and anchor the tree in the ground, right?
Exactly. The root system needs to be able to
grow well beyond the outer edge of the tree's
canopy and go deep into the soil to provide a
good anchor, unfortunately, in a lot of cities.
Things like sidewalks, curves, building foundations,
parking lots, and driveways often really limit
the space available for roots to grow freely.
Right. A strong well -developed root system that's
had plenty of room to grow is probably the most
important thing for a tree's ability to withstand
hurricane winds in a city. So when we're planting
trees in urban areas we need to think just as
much about what's happening underground as we
do about the parts of the tree we can see above
ground. Absolutely and it's not just about the
space available for roots. The qualities of the
soil itself matter too. Things like having enough
soil depth at least three feet. in most cases,
a deep water table and soil that isn't too compacted.
all contribute to healthy and extensive root
systems, which means better wind resistance trees
planted in shallow or heavily compacted soils,
especially if they don't drain well or have a
high water table, tend to develop weak and shallow
roots, making them much more likely to be uprooted
in strong winds. And it's not just about the
existing soil conditions. We also need to be
super careful not to damage the roots of trees
that are already there. Right. The network of
roots under a tree's canopy is vital for keeping
it stable. And many of the biggest, most important
support roots are close to the surface, cutting
or damaging these main anchoring roots, especially
within the area under the tree's crown, seriously
weakens the tree's ability to stay upright in
strong winds. It's really important to avoid
damaging roots during any kind of construction.
And a good rule of thumb is to never cut any
roots closer than five times the diameter of
the tree trunk. OK. Once those crucial anchoring
roots are damaged, the tree's stability is compromised,
sometimes beyond repair. This has been incredibly
insightful. It's amazing how complex the impact
of hurricanes on our urban trees really is. Now,
I came across a more reasoned example about Tampa
losing a lot of tree canopy because of hurricanes
in 2024 and how that could lead to rising temperatures
in the city that really brings home the real
world implications of this issue, doesn't it?
It does. The hurricanes in 2024 had a very real
impact on Tampa's urban tree canopy. Early estimates
suggest a loss of up to five percent of the city's
tree cover. Wow. This isn't just about losing
trees. visually, it has real consequences for
the health and environment of the city. Because
mature trees provide so much shade, which is
crucial for keeping cities cooler, especially
during those hot summer months. Exactly. Studies
have consistently shown that the shade from a
healthy tree canopy can reduce surrounding air
temperatures by as much as six degrees Fahrenheit.
That's a lot. And when you consider that summer
temperatures in Tampa often get into the 90s,
a six degree difference is huge. It can really
affect how comfortable people are, how much energy
they use. for cooling and even public health.
So losing that much tree cover is expected to
make temperatures in Tampa even hotter. That's
what's expected. And unfortunately, efforts to
replant and restore Tampa's lost trees have been
made harder because of cuts to federal grant
funding, which makes it tougher for the city
to invest in the tree planting and care needed
to counteract those potential temperature increases.
This situation really shows how widespread and
long lasting the effects of hurricane damage
can be on our cities. And it highlights how important
it is to plan ahead and have the money for effective
recovery and building long term resilience. It's
a powerful reminder that the impact of these
storms goes way beyond the immediate effects
of wind and rain. The health and extent of our
urban forests play a vital role in the well -being
of our communities. For sure having healthy and
thriving urban forests provides so many benefits
to our communities from shade and cooling to
cleaner air and water and just making life better
for residents when those trees are damaged or
lost because of natural disasters like hurricanes.
The negative effects can last for years. So as
we can see the impact of hurricanes on trees
is a multifaceted issue with immediate and long
-lasting consequences for our urban environments.
Everything from the traits of different tree
species to how they're planted and cared for
influences their ability to withstand these incredible
powerful storms. And as we've learned with Tampa,
losing those trees can even have a measurable
effect on a city's climate. Understanding these
complex dynamics isn't just for arborists and
city planners. It empowers each of us to make
smarter choices about the trees in our yards
and in our communities, helping to create a more
resilient and sustainable urban environment for
the future. We encourage you to really look at
the trees around you and maybe even explore the
specific wind -resistant tree species recommended
for your area. Yeah. It seems like a small thing,
but it can make a big difference when we face
these severe weather events. Absolutely. For
more deep tives into different weather phenomena
and how they affect our world, be sure to follow
meteorologist Rob Jones on Instagram, meteorologist
on TikTok, TV meteorologist, and subscribe to
Rob Jones Hurricane on YouTube. You can find
the Meteorology Matters podcast playlist there.
Sounds great. Keep exploring the fascinating
world around us, keep learning new things, and
we'll see you next time on the Meteorology Matters
podcast. Here's a final thought for you to consider
given everything we've talked about today about
how vulnerable older trees are in hurricane -prone
areas. How can communities strike a balance between
the beauty and historical significance of large
mature trees and the growing safety risks they
might pose in a changing climate that could bring
us more frequent and stronger storms? It's a
tough question without any easy answers, but
it's one that communities will probably need
to address more and more in the coming years.
Thank you for listening to Meteorology Matters.
See you next time.