What are you most squeamish about? Giant cockroaches, spiders, centipedes, scorpions, beetles or even moths?

Me, I'd say most of them, especially if they were the size of a hand or more. Luckily, most of the biggest bugs on our planet are usually found in jungle rainforests, savannahs and caves, or in the safety of our Museum collections.

However, this summer, some of our largest and heaviest insect and arachnid specimens are being let out to star in the Big Bugs exhibition at our Natural History Museum at Tring which opened yesterday and runs until 21 November.

The Australian rhinoceros cockroach is the heaviest cockroach in the world. A female was recorded at just over 1 oz (33.45gms).

From the safety of their exhibition display cases, despite my squeamishness, like many others I will find these mega mini-beasts utterly mesmerising to behold, and highly recommend a visit to Big Bugs. The exhibition is free.

Live creatures like the venomous Emperor scorpion and world's longest stick insect at 14 inches, are on show alongside many rare and incredible specimens from the Natural History Museum's collection. It's the first time that all these enormous bug specimens have been displayed together.

And it's not just the scary bugs and spiders you'll meet, but eye-catching beauties like the delicate Helicopter damselfly and Queen Alexandra's Birdwing butterfly, the largest butterfly in the world.

There will also be creepy-crawly activities for kids at the exhibition and other bug-related activities at Tring throughout the summer season.

The docile giant leaf bush-cricket from New Guinea has a maximun wingspan of 11 inches

The inspiration behind the exhibition is a recently published Museum book, Big Bugs Life-size by our Museum entomologist and bug expert, George Beccaloni, which features actual life-size pictures of each marvellous mini-beast included.

My favourites in the book are the nocturnal rhinoceros cockroach, which is the world's heaviest cockroach, and the giant leaf bush cricket with a wing span of a whopping 11 inches. But the white witch moth, below right, tops that with 12 inches and the greatest wingspan of any living insect.

Read the news story about the Big Bugs exhibition and book

The Natural History Museum at Tring is located in Hertfordshire.

Explore insects and spiders on our website. You can identify and discuss bugs on our bug forum

I'm completely in awe of trees. Especially the trees that flourish, magically, amidst the concrete and bricks, and the metal, rubber and glass of London's busy streets, where I live and work.

So I'm very happy to be telling you about our new online Urban tree survey. This nationwide survey, that launched on Friday 16 July, will be one of the biggest tree surveys ever.

A Judas tree in Cambridge © Andrew Dunn. This was our Species of the day to mark the launch of the Urban tree survey.

Although we know a lot about Britain's rural tree population, relatively little is known about the trees in urban areas. We're being invited to record particularly what's in our private gardens and local streets and parks of urban Britain, so our scientists and botanists can build a picture of what trees are growing where, and also find out how the urban tree population is changing.

Our survey focuses on 80 different types of tree normally associated with an urban environment.

I'm told that one of our most widespread trees is the sycamore, and in urban areas, the closely related norway maple may be as common or more so. These species were introduced to the UK. But we don't have actual numbers for the most common trees, only data on which are most widespread.

There are lots of resources on the Urban tree survey website to help with tree identification and advice on how to take part in the survey.

I recommend watching the Identify trees video first, which shows you what things to look out for to identify your trees correctly. Especially enjoyable because it's filmed in Holland Park, one of London's best parks in my opinion.

To record your findings on the survey, choose an area you want to survey first, and think about the things you'll need to consider before you start recording your trees. For example, are the tree leaves hairy? Are they needle-like or scale-like, broad or lobed? What about fruits or cones? Petals, twigs, bark and importantly what does it smell like? The Tree identification key which you can download and take with you, will help with all this. You can check your identification using our online interactive identification key.

Read the news story about the Urban tree survey for some fascinating facts about the survey and our knowledge of trees.

Explore the lovely Judas tree Species of the day that marked the launch of the survey and is the main photo above. It's also featured in the survey. Now where did it get its name, I wonder?

Are these leaves from an elder or ash? Check your tree knowledge on the survey's ID key chart

The Urban tree survey will run for 3 years and our Cherry tree survey launched this spring is part of it.

Leaves image © Università di Trieste, Dipartimento di Biologia. Photo: Andrea Moro